animal behavior
clock | September 27, 2006Mother Birds Give A Nutritional Leg Up To Chicks With Unattractive Fathers:
Mother birds deposit variable amounts of antioxidants into egg yolks, and it has long been theorized that females invest more in offspring sired by better quality males. However, a study from the November/December 2006 issue of Physiological and Biochemical Zoology shows that even ugly birds get their day. Providing new insight into the strategic basis behind resource allocation in eggs, the researchers found that female house finches deposit significantly more antioxidants, which protect the embryo during the…
clock | September 27, 2006I saw this ScienceDaily report earlier today and thought: "What's new?" I recall a study with similar conclusions from just a couple of months ago, and even that was not that new - I used the example in teaching about 5-6 years ago (then dropped the example as the literature got more and more contentious).
But a few minutes ago, Afarensis posted about this and cleared it up for me - the previous study was from zoos and this one is from the wild. Also, the new study incorporates ontogenetic data - the effects of age.
So, the size and color of the lion's mane is not driven by sexual selection…
clock | September 26, 2006Parasitic Wasps Protect Offspring By Avoiding The Smelly Feet Of Ladybirds:
Scientists at Rothamsted Research have identified how aphid parasitic wasps prevent their offspring being eaten by ladybirds. The tiny wasps implant their offspring parasitically into aphid pests, but should the aphid get eaten by a ladybird, the growing wasp would be consumed as well. The researchers, supported by the Biotechnology and Biological Sciences Research Council (BBSRC), have found that to protect their offspring, adult wasps have evolved to avoid the smell of a short-lived blend of chemicals that ladybirds…
clock | September 25, 2006Fruit Fly Aggression Studies Have Relevance To Humans, Animals:
Researchers in the North Carolina Sate University genetics department have identified a suite of genes that affect aggression in the fruit fly Drosophila melanogaster, pointing to new mechanisms that could contribute to abnormal aggression in humans and other animals.
The study, led by doctoral student Alexis Edwards in the laboratory of Dr. Trudy Mackay, William Neal Reynolds Professor of Genetics, appears online in PloS Genetics.
Feisty flies themselves may not be very scary, but their genes and biochemistry have more in common…
clock | September 24, 2006Wild Bees Make Honeybees Better Pollinators
How?
By sexual harrassment!
Wild bees behave like the male audience of Girls Gone Wild - obnoxious and aggressive. So, the honeybees keep running away from them - from flower to flower.
Winners: Flowers.
Seriously:
Compared to honeybees, wild bees did not contribute much directly to crop pollination. But on farms where wild bees were abundant, honeybees were much more effective in pollinating flowers and generating seeds, Greenleaf found.
There appear to be two reasons for that. Male wild bees, probably looking for mates, will latch onto worker…
clock | September 20, 2006Bird Moms Manipulate Birth Order To Protect Sons:
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Since 2002, Badyaev, Oh and their colleagues have been intensively documenting the lives of a population of house finches (Carpodacus mexicanus) on the UA campus.
Throughout the year, the researchers capture birds several times a week to band and measure them and to take DNA and hormone samples. During the breeding season, the researchers locate the nests, keep track of activity in the nest, follow nestling growth and development, and take DNA samples from the chicks.
The researchers have also been…
clock | September 20, 2006Paramecia Adapt Their Swimming To Changing Gravitational Force:
The researchers placed a vial with pond water and live paramecia inside a high-powered electromagnet at the National High Magnetic Field Laboratory in Tallahassee, Fla. The organisms are less susceptible to a magnetic field than plain water is, so the magnetic field generated inside the vial "pulls" harder on the water than on the cells. If the field is pulling down, the cells float. If it's pulling up, they sink.
Using water alone, Valles and Guevorkian were able to increase the effect of gravity by about 50 percent. To increase…
clock | September 18, 2006In this post from April 06, 2006, I present some unpublished data that you may find interesting.
Understanding the role of serotonin in depression has led to development of anti-depressant drugs, like Prozac. Much of the research in this area has been performed in Crustaceans: lobsters and crayfish. The opposite behavioral state of depression, something considered a normal state, could possibly best be described as self-confidence.
Self-confidence is expressed differently in different species, but seems to always be tied to high status in a social hierarchy. In crayfish, self-confidence is…
clock | September 17, 2006It's looking good. Certainly much smaller than the roomful of metal we are used to seeing in hospitals.
Do you remember when computers used to fill entire rooms? Now take a look at your cell phone. Now think MRI in 10-20 years...
See what I'm getting at?
I am patiently waiting for the time when MRIs are small and light enough to be mounted on heads of freely behaving animals (in the wild or in captivity), at least large animals like elephants, dolphins, horses, crocs or sharks... Then you use radiotelemetry to get the info loaded on your computer and you observe the brain activity in…
clock | September 13, 2006One of the coolest parasites ever (from February 04, 2006):
I am quite surprised that Carl Zimmer, in research for his book Parasite Rex, did not encounter the fascinating case of the Ampulex compressa (Emerald Cockroach Wasp) and its prey/host the American Cockroach (Periplaneta americana, see also comments on Aetiology and Ocellated).
In 1999, I went to Oxford, UK, to the inaugural Gordon Conference in Neuroethology and one of the many exciting speakers I was looking forward to seeing was Fred Libersat. The talk was half-hot half-cold. To be precise, the first half was hot and the second…
clock | September 12, 2006Baby bugs team up for sex scam
The moment they're born, beetles of one species join forces for a curious drill.
The larvae hatch out of their eggs and together, as a group, climb to the tip of the plant. There, they secrete a sex pheromone that attracts a male of a bee who tries to couplate with the ball of larvae. They jump on him. He flies away carrying the little buggers.
When he finds a female to mate with, the larvae jump ship and go away hithhiking on her. When she goes back to her nest they disembark, eat the nectar she collected and her eggs before their final metamorphosis.…
clock | September 12, 2006Scientists discover molecule behind birds' magnetic sense:
"Some birds, notably migratory species, are able to detect the Earth's magnetic field and use it to navigate. New results from a team of Franco-German researchers suggest that light-sensitive molecules called cryptochromes could be the key to the birds' magnetic sense.
They did not suggest it - they tested a 10-year old hypothesis.
Cryptochromes are photoreceptors which are sensitive to blue light, and they are involved in a number of processes linked to the circadian cycle, such as growth and development.
Caution: cryptochromes have…
clock | September 10, 2006'Empty Nester' Parent Birds Use Recruitment Calls To Extend Offspring Care:
By studying a habituated population of pied babblers (Turdoides bicolor) in the Kalahari Desert, researchers have discovered a surprising new way in which parent birds can extend the period of their care of offspring.
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It is well known that birds feed their young directly, but it is usually assumed that care ends when the young leave the nest and begin to forage for themselves. In many species, however, parents and young continue to associate with one another beyond this point of…
clock | September 5, 2006
Hypotheses leading to more hypotheses (from March 19, 2006 - the Malaria Day):
I have written a little bit about malaria before, e.g, here and here, but this is my special Malaria Action Day post, inspired by a paper [1] that Tara sent me some weeks ago and I never got to write about it till now.
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In a journal called "Medical Hypotheses" Kumar and Sharma [1] propose that jet-lagged travellers may be more susceptible to getting infected with malaria. They write:
Rapid travel across several time zones leads to…
clock | September 4, 2006If you are interested in the pros and cons of cannibalism in praying mantises, you should check out the latest Carl's post and article on the topic.
clock | September 4, 2006Chris Chatham of Developing Intelligence blog wrote an excellent summary of the controversy over dolphin intelligence and adds his own thoughts on the matter, with which I agree:
In conclusion, there are countless reasons to doubt that dolphins are "dumber than goldfish," or indeed that popular musings about dolphin intelligence have been inaccurate. Of course, as Cognitive Daily points out, it is clear that they don't have human-level intelligence - whatever that may mean. On the other hand, Manger has developed a new theory about the evolution of the dolphin brain; unfortunately, any…
clock | September 4, 2006Power Emerges From Consensus In Monkey Social Networks:
Research on communication typically focuses on how individuals use signals to influence the behavior of receivers, thus primarily focusing on pairs of individuals. However, the role communication plays in the emergence of social structures is rarely studied.
In a new paper from The American Naturalist, Santa Fe Institute researchers Jessica Flack and David Krakauer study how power structures arise from a status communication network in a monkey society. Power structure is important because it can influence the complexity of interactions…
clock | August 31, 2006Chimpanzees Can Transmit Cultural Behavior To Multiple 'Generations':
Transferring knowledge through a chain of generations is a behavior not exclusive to humans, according to new findings by researchers at the Yerkes National Primate Research Center of Emory University and the University of St. Andrews, Scotland. For the first time, researchers have shown chimpanzees exhibit generational learning behavior similar to that in humans. Unlike previous findings that indicated chimpanzees simply conform to the social norms of the group, this study shows behavior and traditions can be passed along…