headline of the day

Humans Aren't Much Smarter than Dogs

…cognitive scientists gave monkeys and college students a series of very simple tests to determine how quickly and accurately they could add up the number of dots on a screen. On average, the monkeys and students answered in the same amount of time. The students were 94 percent accurate in their answers, while the monkeys were 76 percent accurate. So monkeys are nearly as good as humans at adding dots, even without the benefit of a college education.

What struck me first on contemplating these studies is that cognitive science has taken us in an unforeseen direction. This is a field that promises to study consciousness as if it were a machine, to look at thoughts as electrical impulses and biological structures rather than sublime metaphysics. It would seem, therefore, to run the risk of dehumanizing us, of converting all of our crazy, ambivalent feelings into mere blips on a chart. Instead, what cognitive science has done, at least in these studies, is show us how deeply connected we are to the living creatures around us.

By breaking down our thought processes into their component parts -- pattern recognition, counting -- we are able to see that the building blocks of thought are not unique to Homo sapiens. Dogs and monkeys are doing this shit too.

escaped tiger kills

[collage by doug millison]

now that they're gone, what do we do?

…from the BBC:

Humans 'drive out large mammals'

American bison are one of the species most affected by humans

Almost 80% of the Earth's surface has experienced a sharp fall in the number of large mammals as a result of human activities, a study suggests.

By examining records dating back to AD1500, US researchers found that at least 35% of mammals over 20kg had seen their range cut by more than half.

They said urgent action was needed to protect the animals, which were being hunted or suffering habitat loss.

The findings have been published in the Journal of Mammalogy.

The research, carried out by a team of scientists from Princeton University and conservation group WWF-US, has been described as the first "measurement of human impacts on biodiversity based on the absence of native, large mammals".

"Perhaps the most striking result of our study is that [the] 109 places that still retain the same roster of large mammals as in AD1500 are either small, intensively managed reserved or places of extremes," revealed lead author John Morrison, WWF-US's director of conservation measures.

"Remote areas are either too hot, dry, wet, frozen [or] swampy to support intensive activities."

'Eco-engineering'

The researchers compared the current ranges of the world's largest 263 land mammals with their distribution 500 years ago.

We can now pinpoint places where large mammals assemblages still play important roles in terrestrial ecosystems Eric Dinerstein, WWF chief scientist

The species that suffered the greatest loss were "habitat generalists", including tigers, leopards, lions, American bison, elk and wolves.

Geographically, Australasia fared best, holding on to 68% of its large mammals. At the other end of the scale, South-East Asia only had 1% of the mega fauna that roamed the region in AD1500.

In their paper, the scientists explained why large mammals were so important for maintaining the ecological equilibrium.

"Large carnivores frequently shape the number, distribution and behaviour of their prey," the researchers wrote.

"Large herbivores function as ecological engineers by changing the structure and species composition of surrounding vegetation.

"Furthermore, both sets of mammals profoundly influence the environment beyond direct species interactions, such as through [the food chain]."

WWF chief scientist Eric Dinerstein said he hoped the findings would help focus conservation efforts.

"We can now pinpoint places where large mammal assemblages still play important roles in terrestrial ecosystems," he explained.

"Through strategic re-introductions - such as returning wolves to Yellowstone - we can restore... places missing one or two species and recover the ecological fabric of these important conservation landscapes."

"what we have here is a failure to communicate"

Trail of blood apparently led escaped tiger to victims

human researchers come closer to understanding "dolphin"

…from: The Age

While it is already known that dolphins have "signature" whistles that function like a name, little was known about the meaning of the other whistles they make.

By listening in on bottlenose dolphins under water, marine scientist Liz Hawkins found the creatures had specific whistles for certain activities.

When socialising the dolphins tended to make whistles that were flat or rising in tone, but during their travels "sine" whistles that rise and fall were more frequently heard.

The dolphins also made a particular flat-toned whistle when riding the waves created by the research boat, while early work identified a whistle used often by dolphins living off Queensland's Moreton Island when they were on their own.

nonhuman communication

[collage by Morris Armstrong, Jr.]

what does the bear hair say?

…from Montana State University:

Frozen hair holds secrets of Yellowstone grizzlies

December 17, 2007 -- By Evelyn Boswell, MSU News Service

A curious bear investigates the smell of blood near a wire hair snag. (Photo courtesy of Mark Haroldson).

BOZEMAN -- Locks of hair from more than 400 grizzly bears are stored at Montana State University, waiting to tell the tale of genetic diversity in the Yellowstone Ecosystem.

Ranging from pale blond to almost black, the hair is filed in a chest freezer where the temperature is minus-77.8 degrees. Some of the tufts are almost 25 years old.

The hair will head to Canada in a few months to be analyzed at Wildlife Genetics International in Nelson, British Columbia, said Chuck Schwartz, head of the Interagency Grizzly Bear Study Team based at MSU. The team is monitoring the genetic diversity of the Yellowstone grizzlies over time and wants to know when new DNA appears. The team will also compare the Yellowstone bears with those in the Northern Continental Divide Ecosystem where a similar study has been done.

"An objective of the study is to determine if bears from the Northern Continental Divide Ecosystem migrate to the Yellowstone," Schwartz said.

The Northern Continental Divide Ecosystem includes Glacier National Park, parts of the Blackfeet and Flathead Indian Reservations, parts of five national forests, five wilderness areas and Bureau of Land Management property in northwest Montana. The Yellowstone Ecosystem includes Yellowstone and Grand Teton National Parks, six national forests, and state and private land in portions of Montana, Wyoming and Idaho.

An estimated 550 to 600 grizzlies live in the Yellowstone Ecosystem, about twice what it was 20 years ago, but the population currently lacks diversity, Schwartz said.

"We know it's low," he said. "There are concerns about inbreeding and other issues because we don't have new genes flowing into the system on a regular basis."

Field crews from a variety of federal and state agencies plucked the hair the study team is storing, Schwartz continued. Each lock came from somewhere off the bears' shoulders, but the way it was collected varied. Some of the bears died of natural causes or were killed by humans. Other bears were temporarily unconscious while scientists fit them with radio collars or moved them to another location after they'd gotten into trouble. Some bears left hair behind while crawling underneath barbed wire.

"The vast majority of the time, it is routine," Mark Haroldson said of the collection process. Haroldson is a supervisory wildlife biologist with the Interagency Grizzly Bear Study Team. He has collected bear hair since the late 1980s.

Schwartz said researchers in Idaho can tell him if the hair came from one bear or several. They can tell him the bear's gender and whether the hair came from a bear at all. To answer the tougher questions, Schwartz turns to the Wildlife Genetics International, which routinely analyzes hair from grizzlies, black bears, wolverines and other wildlife in Canada and the United States. The Canadian lab examined the grizzly hair from the Northern Continental Divide Ecosystem. It also analyzes hair collected by MSU graduate students in Yosemite National Park in California and Banff National Park in Alberta, Canada.

Bear hair is tricky because the amount of DNA it contains is so small, said Steven Kalinowski, the students' adviser and a conservation geneticist in MSU's ecology department. Jennifer Weldon, manager of the Canadian lab, said dirty hair can challenge some researchers. So can hair that came from a dead animal and spent so much time in the elements that the DNA degraded.

Schwartz said shafts of the Yellowstone hair will eventually return to MSU so he can conduct other tests and have samples available when new study techniques are developed.

eau de snake

Barbara Clucas/UC Davis photo

…press release from University of California, Davis:

Squirrels Use Snake Scent
December 19, 2007

California ground squirrels and rock squirrels chew up rattlesnake skin and smear it on their fur to mask their scent from predators, according to a new study by researchers at UC Davis.

Barbara Clucas, a graduate student in animal behavior at UC Davis, observed ground squirrels (Spermophilus beecheyi) and rock squirrels (Spermophilus variegates) applying snake scent to themselves by picking up pieces of shed snakeskin, chewing it and then licking their fur. Adult female squirrels and juveniles apply snake scent more often than adult males, which are less vulnerable to predation by snakes, Clucas said.

The scent probably helps to mask the squirrel's own scent, especially when the animals are asleep in their burrows at night, or to persuade a snake that another snake is in the burrow. The squirrels are not limited to the use of shed snake skins, said Donald Owings, a professor of psychology at UC Davis who is Clucas' adviser and an author on the paper. They also pick up snake odor from soil and other surfaces on which snakes have been resting, and use that to apply scent. Other rodents have been observed using similar behavior.

Snake-scent application is one of a remarkable package of defenses that squirrels use against rattlesnakes, Owings said. In earlier work, Owings' lab has found that squirrels can: heat up their tails to send a warning signal to rattlesnakes, which can "see" in the infrared; assess how dangerous a particular snake is, based on the sound of its rattle; and display assertive behavior against snakes to deter attacks. In addition, work by Owings' colleague, psychology professor Richard Coss, has demonstrated that these squirrels have evolved resistance to snake venom.

"It's a nice example of the opportunism of animals," Owings said. "They're turning the tables on the snake."

The other authors on the paper, which was published Nov. 28 in the journal Animal Behavior, are Matthew Rowe, Sam Houston State University, Texas, and Patricia Arrowood at New Mexico State University. The work was funded by the National Science Foundation and the Animal Behavior Society.

mental monkey math

…press release from Duke University:

Monkeys Can Perform Mental Addition

DURHAM, N.C.--Researchers at Duke University have demonstrated that monkeys have the ability to perform mental addition. In fact, monkeys performed about as well as college students given the same test.

The findings shed light on the shared evolutionary origins of arithmetic ability in humans and non-human animals, according to Assistant Professor Elizabeth Brannon, Ph.D. and Jessica Cantlon, Ph.D., of the Duke Center for Cognitive Neuroscience.

Current evidence has shown that both humans and animals have the ability to mentally represent and compare numbers. For instance, animals, infants and adults can discriminate between four objects and eight objects. However, until now it was unclear whether animals could perform mental arithmetic.

"We know that animals can recognize quantities, but there is less evidence for their ability to carry out explicit mathematical tasks, such as addition," said graduate student Jessica Cantlon. "Our study shows that they can."

Cantlon and Brannon set up an experiment in which macaque monkeys were placed in front of a computer touch screen displaying a variable number of dots. Those dots were then removed and a new screen appeared with a different number of dots. A third screen then appeared displaying two boxes; one containing the sum of the first two sets of dots and one containing a different number. The monkeys were rewarded for touching the box containing the correct sum of the sets.

The same test was presented to college students, who were asked to choose the correct sum without counting the individual dots. While the college students were correct 94 percent the time and the monkeys 76 percent, the average response time for both monkeys and humans was about one second.

Interestingly, both the monkeys' and the college students' performance worsened when the two choice boxes were close in number.

"If the correct sum was 11 and the box with the incorrect number held 12 dots, both monkeys and the college students took longer to answer and had more errors. We call this the ratio effect," explained Cantlon. "What's remarkable is that both species suffered from the ratio effect at virtually the same rate."

That monkeys and humans share the ability to add suggests that basic arithmetic may be part of our shared evolutionary past.

Humans have added language and writing to their repertoire, which undoubtedly changes the way we represent numbers. "Much of adult humans' mathematical capacity lies in their ability to represent numerical concepts using symbolic language. A monkey can't tell the difference between 2000 and 2001 objects, for instance. However, our work has shown that both humans and monkeys can mentally manipulate representations of number to generate approximate sums of individual objects," says Brannon.

The study was published in the December 2007 issue of the journal PLoS Biology.

[drawing by morris armstrong, jr.]

war of the worlds

[collage by Morris Armstrong, Jr.]

flickr for dogs under development?

…press release from Springer:

Heidelberg, 28 November 2007

Computer savvy canines

New study shows that dogs can classify color photographs and transfer knowledge in computer tests

Like us, our canine friends are able to form abstract concepts. Friederike Range and colleagues from the University of Vienna in Austria have shown for the first time that dogs can classify complex color photographs and place them into categories in the same way that humans do. And the dogs successfully demonstrate their learning through the use of computer automated touch-screens, eliminating potential human influence. The study1 has just been published online in Animal Cognition, a Springer publication.

In order to test whether dogs can visually categorize pictures, and transfer their knowledge to new situations, four dogs were shown landscape and dog photographs, and expected to make a selection on a computer touch-screen.

In the training phase, the dogs were shown both the landscape and dog photographs simultaneously and were rewarded with a food pellet if they selected the dog picture (positive stimulus). The dogs then took part in two tests.

In the first test, the dogs were shown completely different dog and landscape pictures. They continued to reliably select the dog photographs, demonstrating that they could transfer their knowledge gained in the training phase to a new set of visual stimuli, even though they had never seen those particular pictures before.

In the second test, the dogs were shown new dog pictures pasted onto the landscape pictures used in the training phase, facing them with contradictory information: on the one hand, a new positive stimulus as the pictures contained dogs even though they were new dogs; on the other hand, a familiar negative stimulus in the form of the landscape. When the dogs were faced with a choice between the new dog on the familiar landscape and a completely new landscape with no dog, they reliably selected the option with the dog. These results show that the dogs were able to form a concept i.e. ‘dog’, although the experiment cannot tell us whether they recognized the dog pictures as actual dogs.

The authors also draw some conclusions on the strength of their methodology: “Using touch-screen computers with dogs opens up a whole world of possibilities on how to test the cognitive abilities of dogs by basically completely controlling any influence from the owner or experimenter.” They add that the method can also be used to test a range of learning strategies and has the potential to allow researchers to compare the cognitive abilities of different species using a single method.

Reference
1. Range F et al (2007). Visual categorization of natural stimuli by domestic dogs (Canis familiaris). Animal Cognition (DOI 10.1007/s10071-007-0123-2).

dying duck to SF Bay residents: it's my living room, not your toilet

…read it and weep.

research proves that elephants never forget

…from New Scientist:
Elephants can sniff out human friends from foe

moon triggers sex in our distant coral cousins

Corals spawning at night on the Great Barrier Reef
(caption & photo: ARC Centre of Excellence for Coral Reef Studies

…press release from ARC Centre of Excellence for Coral Reef Studies (CoECRS):

19 October 2007

Key Found To Moonlight Romance

An international team of Australian and Israeli researchers has discovered what could be the aphrodisiac for the biggest moonlight sex event on Earth.

An ancient light-sensitive gene has been isolated by researchers from the ARC Centre of Excellence for Coral Reef Studies (CoECRS) that appears to act as a trigger for the annual mass spawning of corals across a third of a million square kilometres of Australia’s Great Barrier Reef, shortly after a full moon.

The genes, known as a cryptochromes, occur in corals, insects, fish and mammals - including humans - and are primitive light-sensing pigment mechanisms which predate the evolution of eyes.

In a new paper published in the international journal Science today, the team, headed by Marie Curie Scholar Dr Oren Levy of CoECRS and the University of Queensland, reports its discovery that the Cry2 gene, stimulated by the faint blue light of the full moon, appears to play a central role in triggering the mass coral spawning event, one of nature’s wonders.

Professor Ove Hoegh-Guldberg, who leads the University of Queensland laboratory in which the genes were discovered, said “This is the key to one of the central mysteries of coral reefs. We have always wondered how corals without eyes can detect moonlight and get the precise hour of the right couple of days each year to spawn.”

What allows corals to spawn simultaneously along the immense length of the Great Barrier Reef - and also in other parts of the world - has been a scientific mystery till now, though researchers knew that tide, water temperature and weather conditions played a part, says Dr Levy. However the remarkable synchronisation of spawning occurring all along the Reef immediately following a full moon suggested that moonlight was a key factor.

Exposing corals to different colours and intensities of light and sampling live corals on reefs around the time of the full moon, Dr Levy found the Cry2 gene at its most active in Acropora corals during full moon nights. “We think these genes developed in primitive life forms in the Precambrian, more than 500 million years ago, as a way of sensing light,” he explains. “The fact they are linked with the system that repairs damage from ultraviolet (UV) radiation suggests they may evolved in eyeless creatures which needed to avoid high daytime UV by living deep in the water, but still needed to sense the blue light shed by the moon to synchronise their body clocks and breeding cycles.” “They are, in a sense, the functional forerunners of eyes,” Professor Hoegh-Guldberg said.

In humans, cryptochromes still operate as part of the circadian system that tunes us to the rhythms of our planet, though their light-sensing function appears lost to us, he went on to explain.

“They play important roles in regulating the body-clocks of many species, from corals to fruit flies, to zebra fish and mice. The proteins they produce are similar to those in humans and other mammals, though they appear to function more like those in the fruit fly,” says Professor David Miller of CoECRS and JCU.

The coral cryptochrome genes were initially identified by Dr Levy and Dr Bill Leggat working with Professor Hoegh-Guldberg (UQ) on Heron Island. Prof. Miller and Dr David Hayward, of the Australian National University, were able to add information on the coral cryptochromes from a large library of coral genes that they have been compiling (so far they have catalogued about 10,000 out of an estimated 20-25,000 genes in coral), and leading circadian clock biologists from Bar-Ilan and Tel-Aviv Universities in Israel played important roles in interpreting the data.

“Many of these genes developed in deep time, in the earliest phases of organised life on the planet,” Dr Leggat says. “They were preserved for hundreds of millions of years before being inherited by corals when they developed about 240 million years ago, and are still found today in modern animals and humans. They are an indicator that corals and humans are in fact distant relatives, sharing a common ancestor way back.”

Whether they have anything at all to do with human associations between the full moon and romance is not known, but cryptochromes probably still play a part in our body clock.

Link to Full Text of the Paper

Image gallery

singing bats

…press release from: Texas A&M University

Researchers studying how singing bats communicate

COLLEGE STATION, Oct. 18, 2007 – Bats are the most vocal mammals other than humans, and understanding how they communicate during their nocturnal outings could lead to better treatments for human speech disorders, say researchers at Texas A&M University.

Thousands of bats native to Central Texas fly overhead each night singing songs of complex syllables – but at frequencies too high for humans to hear.

Texas A&M researcher Michael Smotherman is trying to understand how Mexican Freetail bats organize syllables into songs and how their communication is linked to the brain. “If we can identify those areas in a bat brain [responsible for communication], we can learn more about how a normal [human] brain generates and orchestrates complex communication sequences,” Smotherman says. “And by understanding how that works, we can then come up with testable hypotheses about what might be going on in speech disorders.”

The researchers in Smotherman’s lab are studying two aspects of bat communication. In behavioral studies, they examine sex differences and seasonal variations in communication, and in physiology studies they try to locate the parts of the bat brain active during communication.

Mexican Freetail bats sing mostly in ultrasonic frequencies that are right above the upper limit of human hearing. Humans can sometimes hear little bits of bat songs, however, when parts of syllables drop low enough.

Bats communicate at such high frequencies because of their ability to echolocate, which means they project sound and use the echoes to determine the direction and distance of objects. As the frequency of the bat’s sound gets higher, it can detect a more detailed picture of its surroundings.

Smotherman says Mexican Freetail bats use between 15 and 20 syllables to create calls. Every male bat has its own unique courtship song. The pattern of all courtship songs is similar, but each male bat uses a different syllable in its distinctive song. Bats also use sophisticated vocal communication to draw territorial borders, define social status, repel intruders, instruct offspring and recognize each other.

“No other mammals besides humans are able to use such complex vocal sequences to communicate,” Smotherman says.

The songs bats sing are similar to bird songs. Scientists have understood the link between bird songs and the bird brain for years, but “the architecture of a bird brain is very different from that of a mammal brain,” Smotherman explains, “so it is difficult to apply knowledge about bird communication to human speech.”

The brains of all mammals are organized in basically the same way, so a bat brain has many of the same structures as a human brain. This makes it easier to infer things about human speech from studying bat communication. The researchers’ first goal is to locate the part of the bat brain responsible for singing. “The bat brain has to have some higher vocal center that’s responsible for organizing these [vocal] sequences and patterns, and we just don’t know where it is yet,” Smotherman says. “So we’re using molecular techniques to identify which regions of the brain are most active during singing.”

Smotherman and his team maintain about 75 bats in their lab. They usually collect the bats from schools and churches that report bats in their buildings. “[By doing this,] we don’t have to feel like we’re taking them out of the wild,” Smotherman says. He adds that the bats are not aggressive and are a “fantastic bat for the lab because they are quite friendly.”

Smotherman hopes that over the next decade, the group can apply its research to knowledge of human speech and help shed light on language disorders. “The fact that human speech is so unique has really constrained research in this area,” Smotherman says. “Compared to other areas of neuroscience, we’re way behind in understanding even the most basic issues of how [speech] works.”

###

600 million years looking for light

UCSB researchers discover the dawn of animal vision

(Santa Barbara, Calif.) -- By peering deep into evolutionary history, scientists at the University of California, Santa Barbara have discovered the origins of photosensitivity in animals.

The findings are published in this week’s issue of the scientific journal PLoS ONE. The scientists studied the aquatic animal Hydra, a member of Cnidaria, which are animals that have existed for hundreds of millions of years. The authors are the first scientists to look at light-receptive genes in cnidarians, an ancient class of animals that includes corals, jellyfish, and sea anemones.

“Not only are we the first to analyze these vision genes (opsins) in these early animals, but because we don’t find them in earlier evolving animals like sponges, we can put a date on the evolution of light sensitivity in animals,” said David C. Plachetzki, first author and a graduate student at UC Santa Barbara. The research was conducted with a National Science Foundation dissertation improvement grant.

“We now have a time frame for the evolution of animal light sensitivity. We know its precursors existed roughly 600 million years ago,” said Plachetzki.

Senior author Todd H. Oakley, assistant professor of biology at UCSB, explained that there are only a handful of cases where scientists have documented the very specific mutational events that have given rise to new features during evolution.

Oakley said that anti-evolutionists often argue that mutations, which are essential for evolution, can only eliminate traits and cannot produce new features. He goes on to say, “Our paper shows that such claims are simply wrong. We show very clearly that specific mutational changes in a particular duplicated gene (opsin) allowed the new genes to interact with different proteins in new ways. Today, these different interactions underlie the genetic machinery of vision, which is different in various animal groups.”

Hydras are predators, and the authors speculate that they use light sensitivity in order to find prey. Hydra use opsin proteins all over their bodies, but they are concentrated in the mouth area, near the tip of the animal. Hydras have no eyes or light-receptive organs, but they have the genetic pathways to be able to sense light.

hungry birds follow attacking army ants

…from LSU:

LSU professor studies army-ant-following birds
Certain tropical birds entirely dependent on ant swarms to flush out prey

BATON ROUGE – In the jungles of Central and South America, a group of birds has evolved a unique way of finding food – by following hordes of army ants and letting them do all the work.

Robb Brumfield, assistant curator of genetic resources at the LSU Museum of Natural Science and assistant professor of biological sciences, first witnessed this peculiarity in 1989 when he accompanied then-LSU graduate student Ken Rosenberg to Peru as an assistant.

“Rosenberg’s project investigated dead-leaf-foraging, which is a specialized way that some tropical bird species have devised to find food. These species find their insect prey by probing dead, curled leaves suspended in vine tangles,” Brumfield said. But as he walked endless jungle trails each day in search of these dead-leafing birds, he became captivated by another novel approach some applied to hunting for food: army-ant following.

With this type of specialization, flocks of birds track army-ant swarms through the forest. “When millions of these army ants are on the move, they consume every insect, spider and lizard they come across,” said Brumfield. “Naturally, any animal that hears them coming – and they’re very, very loud – runs the other way. The army-ant-following birds have learned to take advantage of the swarm by perching above it and preying on insects and other small animals trying to escape. It’s reminiscent of the mockingbird that follows me when I’m mowing the grass, picking off the insects that had been hiding there.”

Now, nearly 20 years after that first trip to Peru, Brumfield has again teamed up with Rosenberg, who is now at Cornell University’s Laboratory of Ornithology, along with Jose Tello of the American Museum of Natural History and three other LSU researchers – Matt Carling, Zac Cheviron and Nanette Crochet – to study the evolution of army-ant following.

“Over the last 50 years there has been some outstanding work on the ecology and behavior of army-ant-following birds, but the details of how the specialization evolved had not yet been examined,” Brumfield said.

The team published their findings in this month’s issue of “Molecular Phylogenetics and Evolution.”

“Using a hypothesis of the evolutionary relationships among antbird species that we reconstructed from DNA gene sequences, what we found is that army-ant following has been around a long time, possibly as long as six million years, and that its evolution followed a logical progression from least specialized to most specialized,” said Brumfield.

There are three main categories of specialization found in army-ant-following birds. The first, called occasional army-ant followers, are the most casual of the three, utilizing the insects to round up food but only as the swarm passes through their territory. Regular army-ant followers, the next level up in specialization, will follow the army ants outside of the flock’s territory but are not completely dependent on the ants to provide food. These birds regularly hunt for themselves. The final, and perhaps most interesting, category is that of the professional army-ant followers. These birds are completely reliant on the army ants for food, presenting a problem almost as unique as the situation itself.

“These birds depend almost solely on one species of army ant, called Eciton burchellii,” said Brumfield. “This makes the professional army-ant followers sensitive to many of the very real threats to this ecosystem, like deforestation, global warming and other similar issues. If anything affects the ant population, it could be devastating for these birds. But what is perhaps most surprising is that, despite the bird’s dependence on one primary ant species, the specialization has persisted for millions of years.”

looking for nonhuman radio drama

The switch has been thrown on a telescope specifically designed to seek out alien life. Funded by Microsoft co-founder Paul Allen the finished array will have 350 6m antennas and will be one of the world's largest. The Allen Telescope Array (ATA) will be able to sweep more than one million star systems for radio signals generated by intelligent beings. Its creators hope it will help spot definite signs of alien life by 2025.…continues at the BBC: Skies to be swept for alien life

[drawing by doug millison]

headline of the day

Today's winner in the "If Animals Do It, It's Probably OK For US Humans" category:

For honey bee queens, multiple mating makes a difference

concrete jungle honeybees doing just fine

….With the recent unexplained disappearance of 25 percent of the U.S. honeybee population, interest in beekeeping is at an all-time high among city dwellers, said Peter Sinton, president of the San Francisco Beekeepers' Association. Membership in the bee club has nearly doubled to 133 in the last three years, ever since apiaries began reporting cases of colony collapse disorder, shocking hive desertions that today threaten the pollination of $14 billion worth of the nation's fruit and vegetable crops. "It has caused a lot of people to worry about the bees, and think that maybe they could become a beekeeper," Sinton said. "In the ecologically oriented Bay Area, the idea strikes a nice chord."It turns out bees get by just fine in a concrete jungle. They typically forage for pollen in a 3-mile radius of the hive, and can thrive on the city's buffet of imported ornamental plants on balconies and rooftops and the dozens of community gardens that dot the city.…

…read it all in today's San Francisco Chronicle: S.F. beekeepers reap a sweet harvest

"fair play in chimpanzees"

The Max Planck Society reports that, "Unlike humans chimpanzees do not show a willingness to make fair offers and reject unfair ones."

headline of the day

Eavesdropping iguanas heed hawk alarms

…@New Scientist:

Galápagos iguanas may not be able to communicate amongst themselves, but it seems they can still catch the drift of mockingbird conversations. A new study shows that the island lizards – needfully wary of predators – often run to a sheltered location upon hearing alarm calls produced by mockingbirds.

for a change, some straight talk about nonhumans

"They're saying we're endangering the trees when they're planning to chop them down," he said. "It's a big joke."

No joke for the trees, unfortunately, which the speaker, Zachary Running Wolf, "a former Berkeley mayoral candidate" is helping to protect from University of California Berkeley officials who want to cut down a grove of oaks to build a new sports facility.

Read it all: Get out of the trees, judge tells Cal sitters in today's San Francisco Chronicle.

["Wolf in the Garden" by Doug Millison]

let the birds show us how

A variety of migrating birds, as well as bats and even hamsters successfully use a 'magnetic sense' to navigate on long journeys. Now, a new type of sensor developed by scientists in the US could make it possible for humans do the same trick.

from: Magnetic sensor could allow pigeon-style GPS in New Scientist

[Falcon by Doug Millison]

inspirational headline from National Geographic

Birds Can "See" Earth's Magnetic Field

city birds cope best with humans

[drawing by doug millison]




From University of Washington:

City birds better than rural species in coping with human disruption

Birds that hang out in large urban areas seem to have a marked advantage over their rural cousins – they are adaptable enough to survive in a much larger range of conditions.

In fact, new research from the University of Washington suggests that the adaptability of many urban bird species means they don't just survive but actually thrive in what might be considered to be a very challenging environment.

"The urban habitat is usually more severe than the habitats these birds historically occupied. Urban habitats aren't easy, so the birds have to have developed coping mechanisms," said John Wingfield, a UW biology professor involved in the research.

The study was led by Frances Bonier, a postdoctoral researcher in biology at Virginia Polytechnic Institute, who did the work as a UW doctoral student before moving to Virginia Tech. Co-author Paul Martin, now an assistant professor of biology at Queens University in Kingston, Ontario, also took part in the research as a UW doctoral student.

Ornithologists, biologists and birdwatchers around the world were sent questionnaires that asked them to list 10 common native breeding birds found in their cities. The responses produced data on 217 urban bird species from 73 of the world's largest cities and 247 rural species. To be considered "rural," a species could not be described as breeding in human-disturbed habitats such as towns and cities, and its natural breeding distribution must overlap at least one of the large cities, implying that at one time the species occupied the area where the city is now.

Some birds on the urban list – starlings, parrots, crows, sparrows, pigeons and doves – would be expected to be found in cities, Bonier said. However the researchers only looked at species native to a particular area, so starlings and sparrows native to Europe but found in North American cities, for example, did not count. Less-common species found in cities included the black-tailed trainbearer, a tiny hummingbird in Quito, Ecuador; the green bee-eater found in Giza, Egypt; and a small bird called the broad-billed tody that lives in Santo Domingo, Dominican Republic, and is part of a group of birds found only in the Caribbean.

The researchers learned that urban birds worldwide can endure a far broader range of environments than rural species. Urban species had elevation ranges more than 1,600 feet broader and their distribution covered about 10 degrees more of latitude, or about 700 miles.

"This sounds very intuitive, but there's never been any research confirming urban birds' adaptability," Wingfield said. "Fran's idea to send out the questionnaires provided the information that we lacked. This now gives us a hypothesis to work from for further research."

The work, supported in part by the National Science Foundation, is detailed in a paper that has been published online and will appear later this year in the print edition of the Royal Society journal Biology Letters. The Royal Society is the United Kingdom's national science academy.

While it is not exactly clear what allows some species to flourish in urban settings, the research supports previous findings that suggested the most specialized birds will have the hardest time adapting in an ever-changing world.

"In the face of global climate change and human disturbances, such as increased urbanization and deforestation, we may be able to identify species that can cope with such changes," Wingfield said. "Then we may be able to identify the species that cannot cope with these changes, or might even go extinct in the face of increased disruption."

The information could be used to fine-tune conservation efforts to save those challenged species, he said.

"Land managers can use the information to determine where trails should go, how many people should be on those trails and similar issues," he said.

###

"plants are not boring and passive organisms that just stand there waiting to be cut off or eaten up"

…reports the Nederlands Organization for Scientific Research:

Clever plants chat over their own network

4 September 2007

Recent research from Vidi researcher Josef Stuefer at the Radboud University Nijmegen reveals that plants have their own chat systems that they can use to warn each other. Therefore plants are not boring and passive organisms that just stand there waiting to be cut off or eaten up. Many plants form internal communications networks and are able to exchange information efficiently.

Many herbal plants such as strawberry, clover, reed and ground elder naturally form networks. Individual plants remain connected with each other for a certain period of time by means of runners. These connections enable the plants to share information with each other via internal channels. They are therefore very similar to computer networks. But what do plants want to chat to each other about?

Recently Stuefer and his colleagues were the first to demonstrate that clover plants warn each other via the network links if enemies are nearby. If one of the plants is attacked by caterpillars, the other members of the network are warned via an internal signal. Once warned, the intact plants strengthen their chemical and mechanical resistance so that they are less attractive for advancing caterpillars. Thanks to this early warning system, the plants can stay one step ahead of their attackers. Experimental research has revealed that this significantly limits the damage to the plants.

However there are two sides to the coin. That is not just the case for the Internet but also for plants. It appears that plant viruses can use the infrastructure present to rapidly spread through the connected plants. The infection of one plant therefore leads to the infection of all plants within the network.

This research clearly reveals that the general image of plants is a poor reflection of reality. Who had now suspected that the majority of plants around us are constantly internetting?

This research is part of the Vidi project 'Plant Intranets. Costs, benefits, & risks of communication pathways in clonal plant networks' that was funded by NWO and the Radboud University Nijmegen.

Image: Clover plants can warn each other via a network of runners.

elephant god ganesh playing veena

…from the Ganesh in Indian Art site, which also features an article, The King of Sets, about the god:

Ganesh or Ganapati (translated as the King of sets) is the elephant headed son of Lord Shiva and is widely worshipped by the Hindus. He is the God of the Beginning (so much so that to Ganesh is to begin in many Indian languages), the God of elimination of troubles, and a deity who is easily pleased (with good food).

Ganapati is considered god of wisdom in mythology. Though name "Ganapati" appears in Rigveda, he is not the same God who is worshipped as elephant-headed God today. "Gana" represents a clan and "Pati" is considered chieftain. In Vedic times, image worship did not exist and "Ganapati" stood for Brihaspati or Brahmin. The concept of Ganapati as elephant-headed God evolved in later age. In Hindu mythologies, every deity has a animal vehicle of his own and Lord Ganesh has mouse as his vehicle!

The elephant in Indian ethos occupies significant place. Due to its enormous strength, huge form, sharp memory an cleverness, Indians who visualize divinity in all living creatures naturally ascribe super qualities in this great animal. In our vast tropical forests, roaming elephant herds are led by powerful youthful elephant who commands respect for young and old ones. Among early Aryans and native tribes, elephants evoked fear and respect and it did not take long to conceptualize elephant God who was full of contrasts. For a heavy god, with enormous body and appetite, he rides a small mouse! He has big ears, and small eyes. For his super intellect and sharp memory, he is humble and serves as a scribe to great Vyasa who wrote (dictated) the Mahabharata. He is considered Ameya (beyond measure), and Aprameya (beyond visualization (riddles)). It is perhaps only to represent omniscience form of Almighty that Ganesh is worshipped.

alex approaches the zero

…from the New York Times:

September 16, 2007
Parrot Power
Alex Wanted a Cracker, but Did He Want One?
By GEORGE JOHNSON

IN “Oryx and Crake,” Margaret Atwood’s novel about humanity’s final days on earth, a boy named Jimmy becomes obsessed with Alex, an African gray parrot with extraordinary cognitive and linguistic skills. Hiding out in the library, Jimmy watches historical TV documentaries in which the bird deftly distinguishes between blue triangles and yellow squares and invents a perfect new word for almond: cork-nut.

But what Jimmy finds most endearing is Alex’s bad attitude. As bored with the experiments as Jimmy is with school, the parrot would abruptly squawk, “I’m going away now,” then refuse to cooperate further.

Except for the part about Jimmy and the imminent apocalypse (still, fingers crossed, a few decades away), all of the above is true. Until he was found dead 10 days ago in his cage at a Brandeis University psych lab, Alex was the subject of 30 years of experiments challenging the most basic assumptions about animal intelligence.

He is survived by his trainer, Irene Pepperberg, a prominent comparative psychologist, and a scientific community divided over whether creatures other than human are more than automatons, enjoying some kind of inner life.

Skeptics have long dismissed Dr. Pepperberg’s successes with Alex as a subtle form of conditioning — no deeper philosophically than teaching a pigeon to peck at a moving spot by bribing it with grain. But the radical behaviorists once said the same thing about people: that what we take for thinking, hoping, even theorizing, is all just stimulus and response.

Was Alex only parroting when he showed off for Alan Alda on “Scientific American Frontiers” (one of the PBS productions the fictional Jimmy might have seen)?

“What color smaller?” Dr. Pepperberg asked the parrot as she held up two keys. “Green,” he responded. Alex also seemed to understand concepts like “bigger,” “different” and “same.” Presented with a tray of colored cutouts — the numerals 1 to 6 — he could tell you which one was gray: “Four.”

Many linguists argue that only human brains have the ability to nest ideas within ideas to form the infinitely recursive architecture of thought: When you’re done eating breakfast would you look in the box at the back of the table for the yellow rubber glove with the middle finger turned inside out?

Alex could pull together a few simple concepts. Show him a group of objects and he could tell you, “What color is wood and four-corner?” or, “What shape is paper and purple?” Dr. Pepperberg was hoping to train Alex to spin his own recursions, informing her that the nut was “in the blue cup that’s on the tray” or “in the yellow box on the chair.”

“I wish we had gotten further,” Dr. Pepperberg wrote in an e-mail message. “We were just beginning to get him to designate things like ‘in’ and ‘on.’ ”

The deepest recursion is consciousness — knowing that you know and that you know that you know. In his recent book, “I Am a Strange Loop,” Douglas Hofstadter proposed that the richness of a creature’s mental representations be used to take the measure of its soul.

The unit Dr. Hofstadter whimsically proposed is the “huneker,” named for James Huneker, a music critic who wrote that Chopin’s 11th Étude, in A minor, (Op. 25) was so majestic that “small-souled men, no matter how agile their fingers, should not attempt it.”

If your average person’s soulfulness weighs in at 100 hunekers with a hamster down near 10, Alex hovered somewhere above the halfway mark. But there were moments when he seemed to reach for the top.

In an talk on Edge.org, Dr. Pepperberg told of an effort to teach the parrot about phonemes using colored tokens marked with letter combinations like sh and ch.

“What sound is green?”

“Ssshh,” Alex answered correctly, and then demanded a nut. Instead he got another question.

“What sound is orange?”

“Ch.”

“Good bird!”

“Want a nut!” Alex demanded. The interview was over. “Want a nut!” he repeated. “Nnn ... uh ... tuh.”

Dr. Pepperberg was flabbergasted. “Not only could you imagine him thinking, ‘Hey, stupid, do I have to spell it for you?’ ” she said. “This was in a sense his way of saying to us, ‘I know where you’re headed! Let’s get on with it.’ ”

She is quick to concede the impossibility of proving that the bird was actually verbalizing its internal deliberations. Only Alex knew for sure.

Next to infinity, one of the hardest concepts to grasp is zero. Toward the end of his life Alex may have been coming close.

In a carnival shell game, an experimenter would put a nut under one of three cups and then shuffle them around. Alex would pick up the cup where the prize was supposed to be. If it wasn’t there he’d go a little berserk — a small step, maybe, toward understanding nothingness.

A bigger leap came in an experiment about numbers, in which the parrot was shown groups of two, three and six objects. The objects within each set were colored identically, and Alex was asked, “What color three?”

“Five,” he replied perversely (he was having a bad attitude day), repeating the answer until the experimenter finally asked, “O.K., Alex, tell me, ‘What color five?’ ”

“None,” the parrot said.

Bingo. There was no group of five on the tray. It was another of those high huneker moments. Alex had learned the word “none” years before in a different context. Now he seemed to be using it more abstractly.

Dr. Pepperberg reported the result with appropriate understatement: “That zero was represented in some way by a parrot, with a walnut-sized brain whose ancestral evolutionary history with humans likely dates from the dinosaurs, is striking.”

In a well-known essay, “What Is it Like to Be a Bat?” the philosopher Thomas Nagel speculated about the elusiveness of subjectivity. What was it like to be Alex that last night in his cage? We’ll never know whether there really was a mind in there — slogging its way from the absence of a cork-nut to the absence of Alex, grasping at the zeroness of death.

headline of the day

Scientists warn of 'vocal terror'

"all animals are to be found in men "

From the oyster to the eagle, from the swine to the tiger, all animals are to be found in men and each of them exists in some man, sometimes several at the time. Animals are nothing but the portrayal of our virtues and vices made manifest to our eyes, the visible reflections of our souls. God displays them to us to give us food for thought.

–Victor Hugo, Les Misérables, pt. 1, bk. 5, ch. 5 (1862).

how we see Other

No doubt the thought that was uppermost in a thousand of those vigilant minds, even as it was uppermost in mine, was the riddle--how much they understood of us. Did they grasp that we in our millions were organized, disciplined, working together? Or did they interpret our spurts of fire, the sudden stinging of our shells, our steady investment of their encampment, as we should the furious unanimity of onslaught in a disturbed hive of bees?

-War of the Worlds, H.G. Wells, Ch 15

"despotic" or "egalitarian"? let the computer sort it out

…from: University of Bath

Primate behavior explained by computer 'agents'

The complex behaviour of primates can be understood using artificially-intelligent computer ‘agents’ that mimic their actions, shows new research published in a special edition of Philosophical Transactions of the Royal Society B and presented at the BA Festival of Science in York.

Scientists using agents programmed with simple instructions to work out why some primate groups are ‘despotic’ whilst others are ‘egalitarian’ - overturning previous theories developed by primatologists.

They have also found support for an existing theory of how dominant macaques make it to the safer positions at the middle of their troop without seeming to be pre-occupied with getting there.

Using agents programmed with two rules – stay in a group for safety and pester subordinates until they move away – scientists found that their more dominant agents would make their way to the centre of the group.

This desire to stay in a group and pick on subordinates could be an evolutionary mechanism that helps protect the more dominant and successful individuals in a group, they suggest.

“This kind of agent-based modelling is really a new way of doing science,” said Dr Joanna Bryson from the University of Bath who led the study and is one of the editors of the Philosophical Transactions special edition.

“Previously scientists have been limited to trying to understand animal behaviour by making observations and then developing theories that fit.

“Now we can test these theories using agents to give us a better understanding of complex behaviours.

“This work shows that agent models are an ordinary part of scientific theory building. We confirmed and extended previous work on spatial location of dominant animals, while showing where some theories got it wrong – in this case a theory put forward for why macaques form either despotic or egalitarian troops.”

Whilst there is no hierarchical structure in egalitarian groups there tends to be more fighting, although it is less violent, than in despotic groups.

Primatologists noticed that egalitarian groups tend to spend more time preening and hugging each other after fighting, leading them to speculate that the two different types of society evolved following the development of some groups’ ability to ‘reconcile’.

“Agent-based modelling techniques let us invent and remove behaviours to test the explanations of what we see in nature,” said Dr Bryson, from the University’s Department of Computer Science.

“Using modelling you can vary the external environmental factors to see if they have any effect on behaviour. You can do this for many generations in a few hours and see whether new behaviour is adaptive.”

More recent work by Dr Bryson and graduate student Hagen Lehmann has shown a new explanation for the theory they had previously overturned.

“By changing the amount of space between troop members, you can create models of despotic and egalitarian groups of agents,” said Dr Bryson.

“Then you can show that the despotic agents do better in the conditions we find despotic macaques in the wild. The same holds for egalitarian macaques

“The violence and lack of reconciliation in despotic groups comes down to the fact that they don’t like living on top of each other.

“This creates more space for the troop so they can find more food.

“But by hugging and making up after fights, the egalitarians spend more time close to each other. This makes them safer in environments where there are predators.

“This is a simple explanation for what we see in the wild, and it explains why some groups have a different range of behaviours than another.”

r.i.p. Alex

…press release from The Alex Foundation:

Alex the African Grey parrot and subject of landmark studies of bird intelligence dies at 31

WALTHAM, MA (SEPTEMBER 10, 2007)—Alex, the world renowned African Grey parrot made famous by the ground-breaking cognition and communication research conducted by Irene Pepperberg, Ph.D., died at the age of 31 on September 6, 2007. Dr. Pepperberg’s pioneering research resulted in Alex learning elements of English speech to identify 50 different objects, 7 colors, 5 shapes, quantities up to and including 6 and a zero-like concept. He used phrases such as “I want X” and “Wanna go Y”, where X and Y were appropriate object and location labels. He acquired concepts of categories, bigger and smaller, same-different, and absence. Alex combined his labels to identify, request, refuse, and categorize more than 100 different items demonstrating a level and scope of cognitive abilities never expected in an avian species. Pepperberg says that Alex showed the emotional equivalent of a 2 year-old child and intellectual equivalent of a 5 year-old. Her research with Alex shattered the generally held notion that parrots are only capable of mindless vocal mimicry.

In 1973, Dr. Pepperberg was working on her doctoral thesis in theoretical chemistry at Harvard University when she watched Nova programs on signing chimps, dolphin communication and, most notably, on why birds sing. She realized that the fields of avian cognition and communication were not only of personal interest to her but relatively uncharted territory. When she finished her thesis, she left the field of chemistry to pursue a new direction—to explore the depths of the avian mind. She decided to conduct her research with an African Grey parrot. In order to assure she was working with a bird representative of its species, she asked the shop owner to randomly choose any African Grey from his collection. It was Alex. And so the 1-year old Alex, his name an acronym for the research project, Avian Learning EXperiment, became an integral part of Pepperberg’s life and the pioneering studies she was about to embark upon.

Over the course of 30 years of research, Dr. Pepperberg and Alex revolutionized the notions of how birds think and communicate. What Alex taught Dr. Pepperberg about cognition and communication has been applied to therapies to help children with learning disabilities. Alex’s learning process is based on the rival-model technique in which two humans demonstrate to the bird what is to be learned. Alex and Dr. Pepperberg have been affiliated with Purdue University, Northwestern University, the University of Arizona, the MIT Media Lab, the Radcliffe Institute, and most recently, Harvard University and Brandeis University.
Alex has been featured worldwide on numerous science programs including the BBC, NHK, Discovery and PBS. He is well known for his interactions with Alan Alda in an episode of Scientific American Frontiers on PBS and from an episode of the famed PBS Nature series called “Look Who’s Talking.” Reports on Alex’s accomplishments have appeared in the popular press and international news from USA Today to the Wall Street Journal and the New York Times. The Science Times section of the New York Times featured Alex in a front-page story in 1999. That same year, Dr. Pepperberg published The Alex Studies, a comprehensive review of her decades of learning about learning from Alex. Many other television appearances and newspaper articles followed.

Alex was found to be in good health at his most recent annual physical about two weeks ago. According to the vet who conducted the necropsy, there was no obvious cause of death. Dr. Pepperberg will continue her innovative research program at Harvard and Brandeis University with Griffin and Arthur, two other young African Grey parrots who have been a part of the ongoing research program.

Alex has left a significant legacy—not only have he and Dr. Pepperberg and their landmark experiments in modern comparative psychology changed our views of the capabilities of avian minds, but they have forever changed our perception of the term “bird brains.”

If you choose to help support this research, please consider making a donation in Alex's memory to The Alex Foundation, c/o Dr. Irene Pepperberg, Department of Psychology/MS-062, 415 South Street, Brandeis University, Waltham, MA 02454.

divulge bird talk or divorce: you make the call

There are many instances in our scriptures where ancient Indians had mastered animal languages. While king Kekaya was with his queen, he overheard the conversation of a pair of birds nesting in his courtyard which made, him laugh. He admitted to the queen that he understood birds' talk but refused to share this with others which was a taboo. When the queen insisted to know the contents of the bird's conversation, the king preferred to divorce her on the advice of his guru who had blessed this boon on the king than divulge the code. In Chandogyaupanishat another interesting incident has been mentioned. One evening a pair of cranes were flying back to their place of rest ; the talkative one said to the other that the king Janasbruthi is a very religious and learned person and therefore we must be extra careful while flying over his kingdom. This other crane reacted sharply and asked, "Does this king come anywhere near wisdom of Raikva?" The king overheard this conversation, located Raikva who was relaxing under a bullock cart and learned Bramha-jnana from him.

from:
Animals of Indian Mythology by Dr. Krishnanand Kamat

headline of the day

Role reversal as humans suck life out of leeches

Hard not to feel sorry for the little suckers after reading that story.

she taught her pet pig to play tag and chew gum, and still eats pork

… Oglesby says she's happy with her decision to go with a somewhat unusual pet, despite the challenges in raising it.

"I'm an odd person," she says. "I think I'm a fun person, but I am an odd person. I've just always wanted a pig."

That may be true if you consider teaching a pig to chew gum and play tag. Oglesby says both hidden talents came out of Tater Tot by accident.

"We were just out in the yard and I ran up and touched her one day, then I ran away," Oglesby says. "She kind of danced around for a minute, then she chased me and touched me with her snout, then she ran off. Another time I was just sitting there and I decided to give her a piece of gum."

Don't believe all that stuff you may have read about pigs eating anything.

"She only likes fruit-flavored gums," Oglesby says. "She'll chew it for 10 or 15 minutes until it loses its flavor, then she'll spit it out. My next big thing is teaching her how to blow a bubble."

That's about where Tater Tot's picky palette ends. Except for a distaste for carrots and cucumbers, the little pig will eat just about anything put before her, from table scraps to dog food - her favorite.

"Of course, we don't feed her any pork," Oglesby says. "That would just be wrong."

Oglesby still eats pork, though.

"Yeah, but I can't tell her that," she says. …

…from: One 'Pig' Happy Family by Derek Hodges, The Mountain Press

what do the traces of antique british beaver architecture communicate?

[…] Chapter 4 focuses upon the human exploitation of beaver resources or beaver modified landscapes. Here it is evident that beavers were not just a potential source of food or fur but also that their territories could in addition have provided human populations with readily available kindling, firewood, ‘coppice’ poles and ponds stocked with fish and waterfowl. Dams could also have been used as ‘natural’ crossing points. An interesting observation is that beaver ‘canals’ just might have inspired later human engineering works on floodplains.

Chapters 5 to 12 look at the possible archaeological evidence of beaver activity in the British Isles over the last 15 000 years. Using the modern structures and plans as a guide, the case for features at sites such as at Thatcham (Mesolithic) and West Cotton (Neolithic) being possible beaver structures is carefully and fully explored. It is apparent that from the Neolithic to the Iron Age the evidence for beaver shifts away from beaver ‘structures’ and toward beaver remains, particularly their striking incisors, as tools or ornamentation. Throughout the possibility that archaeological excavation might have created a bias is fully acknowledged.

Can it be that the Romans weren't interested in beaver?

Interestingly evidence for beaver is scant during the Roman period. The possibility is raised that this may actually be due to the relative invisibility of beaver at that time, rather than actual decline. As is also discussed elsewhere in the volume beaver are adaptive, and will only build lodges and dams when stream or river conditions require deepening of water. […]

…from:
Beavers in Britain’s Past by Bryony Coles (WARP Occasional Paper 19). x+242 pages, 158 illustrations. 2006. Oxford: Oxbow; 978-1-84217-2261

reviewed at: http://antiquity.ac.uk/reviews/davies.html

all-spectrum communication

The analysis of communication between individual animals has led to several discoveries of the highest significance. Althgough something simpler was initially expected, communicating signals have turned out, at the very least, to include an announcement that the sender is of given species, sex, and appropriate age, and is in one of a relatively few basic behavioural states, such as readiness for fighting, fleeing or mating (Sebeok and Ramsay, 1969; Hinde, 1972; Smith, in press). These messages also have an intensity scale from weak to strong. Conspecific partners respond to varying degrees and in different ways, but often appropriately according to their own age or reproductive condition. Individual recognition of conspecific companions is common at least in birds and mammals (Falls, 1969; Beer, 1973a, 1973b, 1975, 1976). A frequent element is the flexibility and interrelatedness of the signaling behaviour; fairly complex sequences are performed, with each step depending on an appropriate signal or response from the partner (Griffin, 1976).

The study of animal behaviour brings out the fact that one part of animal activity includes reactions of individuals to informative signals coming from other individuals. Signals are generally defined according to the physico-chemical nature of the stimulus or the sensory properties of the organs which act as detector-receptors. They are chemical (smell), visual (sight), electrical (galvanic sensibility) tactile and kinaesthetic (vibratory sense) and acoustical (hearing).

So almost every sensory system is employed by some species of animals for communication with conspecies. Chemical signals, including pheromones, are ordinarilyy detected by the olfactory system and are especially important in insects, flying phalangers, rodents, cats, and monkeys (Wilson, 1975). Surface waves are used by aquatic insects (Wilcox, 1972). Tactile communication includes not only direct contact between animals, but communication via vibrations of the ground or vegetation. Many groups of fishes that use electrical orientation (Bullock, 1973) also communicate by electrical signaling (Hopkins, 1974; Westby, 1974). Then there is Tanzsprache (dance speech) of bees which is a very complexly received and expressed message system. Sounds are extensively used by many groups of invertebrates, as well as by all classes of vertebrate animals (Sebeok, 1968, 1972). Communication by visual signals too is widespread, but it hasn't been studied as extensively as has acoustical communication, primarly because it is technically more difficult to record and play back visual signals (Griffin, 1976).

Several studies of languagelike communication learned by chimpanzees have taken place. For example chimpanzees are able to learn sign language rather than vocalizations to communicate. The reason for this is suspected to be that the chimpanzees brain is capable of relatively complex communication but that this capability can be expressed far more readily through manual gestures than by vocalization. The extensive observations by Goodall (1968, 1971, 1975) have clearly demonstrated that wild chimpanzees use gestures and facial expressions that are effective but are difficult for human observers to analyze in detail. This shows that the physiological prerequisitions of a species are to be kept in mind when studying the communication of that species. Other animals are largely controlled by their instincts not their free analytic minds, as humans. Different acoustic signals are sometimes triggered by specific hormonal or other activity or vice versa. For example the roar of a lion seems to be not controllable by the lion itself. When started, his muscles are so tensed and his chest under a lot of pressure, so it looks like he must finish in a certain time and not before, because this pressure has a way of natural decay. Also a dog or a wolf doesn't seem to be able to suddenly just close his mouth when howling. Biomusicological aspects should not be left out when studying animal communication and it's musical values. But they are not dicussed more deeplu in this essay though. I leave it to further studies.

Chemical messages have the wildest range, and their remanence enables them to impart lasting information. Visual information is more limited in range because of natural screening caused by vegetation, and also by the sensitivity of the eye. Acoustical message is clearly greater than optical or gestural messages, though sound emission can be parially hindered by climatic conditions. Acoustic message undoubtedly represents the most complete and efacious mode of imparting information, owing to its facility of diffusion, its resistance to disturbances and also to its possibility of creating a vocabulary by a variation of its different parameters. (Dumortier, 1963)

…from:
Communication and Music
Some issues of non-human animal communication. Is there a difference between ordinary communication and musical behaviour
by Kairi Kosk

Elephants communicate with sounds below the range of the human ear.
[drawing by Doug Millison]