Moose antlers help hearing

The big antler racks of moose may help males amplify sounds to better locate females:

http://www.guardian.co.uk/science/2008/mar/21/medicalresearch.animalbehaviour

Researchers used a set of Alaskan moose antlers, and placed a prop ear and a microphone between them, and measured the sound reaching the microphone with and without the antlers. With the antlers, head-on sound was amplified by 19%, but when the antlers were turned away from the sound, it was decreased by 21%, suggesting that they help in direction finding, just like how our external ears (auricles) are directed towards our front.

Secrets of cuttlefish camouflage

Secrets of the Camouflage Masters. Cuttlefish seem to be able to camouflage themselves against any sort of background - rocks and pebbles, corals, even checkerboards. Robert Hanlon of the Woods Hole Marine Biological Laboratory has classified the different cuttlefish camouflage patterns and shown that they fall into three broad categories - uniform colour, mottled colour, and disruptive patterns (like stripes and spots). According to the article: "What he learned from cephalopods may apply throughout the animal kingdom. The fact that cephalopods may need just three camouflage categories could mean that there are just a few basic ways to fool predators." That puts a new spin on the age old problem of animal camouflage and concealment. The question to ask might not be 'why are these animal so good at blending into the background' but rather 'why are we (or why are predators) so bad at spotting these particular kinds of patterns against the background?' A predator-centered approach might need to bring in theories of cognition and pattern-recognition.

One puzzling problem remains, though. Cuttlefish are colour blind yet they can adopt different colours in their camouflage. How do they manage to do so? No one yet knows....

Birdsong and Human Speech

Speech and language seem to be uniquely human traits, which begs the question of how they arose. It turns out that a key regulatory gene controlling human speech, the FOXP2 (forkhead box transcription factor) gene, is also found in other animals, including songbirds. Knocking out these genes in humans (though accidental mutations) results in speech disorders associated with abnormalities in the basal ganglia, though exactly how they control the ability to speak is unknown. A team of German scientists used songbirds as a model for understanding the development of human speech. Instead of simply knocking out the gene, they used RNA interference to reduce FOXP2 levels in a specific area of the basal ganglia, known as Area X, in zebra finches, while they were in the stage of learning their song. This resulted in abnormal song patterns and provides a very persuasive example of how some genes can be directly linked to certain elements of behavior. However, note that the FOXP2 gene is a transcription factor gene that is part of the developmental toolkit, and so functions by regulating the expression of several other genes, so the actual pathway may be much more complicated that it first appears to be, so it would be misleading to simply call FOXP2 the 'speech gene'.

Bacterial Biofilms

This recent article in PLoS Biology gives a very readable review of bacterial biofilms and the kinds of problems they pose in medical settings. A familiar example of a bacterial biofilm is plaque on our teeth. Bacteria, when they reach a certain critical density on a surface, begin to aggregate and secrete a slimy polymeric matrix which aids further establishment and eventually builds up to a complex structure with channels and pores through which fluid can flow, carrying in nutrients and carrying away waste materials.

A few interesting points to think about:

• The means by which the bacteria detect the critical population density needed to form biofilms is called quorum sensing. How does it work?
  
• Previously it was thought that the slimy matrix protected bacteria by preventing them from being engulfed or attacked by other cells or substances, but the matrix has to be permeable to most substances because waste and nutrients must reach the bacteria. So how do they defend themselves?
  
• Biofilms usually form on surfaces over which there is regular fluid flow. Why would the biofilm growth form be advantageous?
  
• Bacteria living in biofilms reproduce at a slower rate than free living ones. How might this be understood by analogy to life-history trait selection in r- and K-selective environments?
  

Advice for alpha-female Hilary Clinton

Frans de Waal, primate ethologist and author of “Our Inner Ape” (2006) decides to weigh in with some recommendations for Hilary Clinton in "Alpha Females I Have Known" (The Huffington Post, 06 Sep 2007). Its based on primate behaviour which may just be what it takes to unravel politics in Washington.

His sugggestions:

1. It'll only get better with age. So far, the typical alpha female is post-reproductive, e.g. Golda Meir, Indira Gandhi, Margaret Thatcher, Angela Merkel. Younger females will distract the process by arousing competition among males.

2. Since males respect power more than age and personality, lead a large coalition by promoting female solidarity. So the earlier point, being sexually non-threatening helps, and be a champion of female causes.

3. Dismiss any inclination to be extremely loyal to friends; reach out beyond the inner circle to build bridges and even groom rivals. Impartiality is tough but sorely needed since the men don't get it (a reference to Bush).

4. Don't listen to clueless designers - don;t emphasise attractiveness or femininity - that's a hat tip to sexual power which won't build a broad coalition (again point 1). Since you have high status, the men are turned off anyway.

Read "Alpha Females I Have Known."

Technorati Tags: behaviour

Chimpanzee behaviour research blog

Alexander Georgiev and colleagues are producing a blog from the Department of Anthropology at Harvard. He writes:

"Currently we've got one of our post-docs in the field in Kibale Forest, Uganda and while there he's writing a blog with news on what he's up to.

Trying to make this broadly educational, we've also got some stuff on the chimps that are studied there - the Kanyawara community. Lots of cool photos, too.The site will be undergoing major changes in the next months so I wanted to get feedback from people: any comments and suggestions would be great.

Do you like the blog as it is? What is it that you'd like to get more info on in particular? Do you think having this kind of 'personal touch' from researchers in the field might be useful in helping students to feel more engaged in the study of animal behaviour in general and chimps in particular? Yes/no - why?

Looking forward to any constructive criticism." - georgiev AT fas.harvard.edu

Link

"First observation of tool use in wild Gorillas"

I first heard this over BBC on the way to NIE. I am so glad its on PLOSBiology. Now at least it can be easily shared.

According to Breuer, Ndoundou-Hockemba and Fishlock (2005), "This paper documents what we believe to be the first two observations of tool use in wild western gorillas (Gorilla gorilla)."

"We first observed an adult female gorilla using a branch as a walking stick to test water deepness and to aid in her attempt to cross a pool of water at Mbeli Bai, a swampy forest clearing in northern Congo. In the second case we saw another adult female using a detached trunk from a small shrub as a stabilizer during food processing. She then used the trunk as a self-made bridge to cross a deep patch of swamp."

Reference: Breuer T, Ndoundou-Hockemba M, Fishlock V (2005). First Observation of Tool Use in Wild Gorillas. PLoS Biol 3(11): e380. Get that PDF here.

The Kakapo breeds

I first heard of the sad story of this strange bird from New Zealand, the kakapo (Strigops habroptilus), in Douglas Adams and Mark Carwardine's (radio series and) book Last Chance to See.

The kakapo, the heaviest parrot in the world (up to 4kg), seemed doomed by its strange breeding habits and the deadly effects of man's intrusion on the islands. The population was whittled down to a mere 50 known individuals by 1995. Their extinction seemed inevitable until a recovery programme was initiated. Now up to 86, there was more good news last week - the kakapo are breeding again and three chicks have been born!

See: Breeding success for rare kakapo. By Kim Griggs, BBC News, 26 Mar 2005. And check the Kakapo Recovery Programme for latest news.

A blog, Another Chance to See tracks the species mentioned in "Last Chance to See" honour of the late Douglas Adams.