News

fruit fly
A fruit fly in flight showing the special sensory organ, the haltere. Courtesy of the BioFuture Research Group, University of Ulm.
New research published in the PNAS shows that fruit flies employ strategies, similar to modern airplanes, to recover their heading after disturbances. Their results show that these small insects use a combination of passive aerodynamic damping forces and active turning forces to recover their original flight heading to within 2° in less than 60 milliseconds.

 

Flies have remarkable aerodynamic abilities and as anybody who has ever tried to smash a fly will know, they can change flight direction very fast in response to an approaching stimulus. A new study now finds that the fruit fly, Drosophila melanogaster, has an equally impressive ability to recover from quick flight disturbances

A new study shows that ants that are about to die from illness leave the company of their nest-mates and socially isolate themselves. Since deadly infections can spread quickly among the thousands of individuals in an ant-nest, this behaviour might have evolved to reduce this risk.

 

Ants are highly social insects that live in colonies ranging from thousands to millions of individual ants, all daughters of the single reproductive queen. Although a social life-style gives many advantages including defence, resource utilization and in ant colonies also in the high degree of specialisation, it also results in increased risks from the easy spread of pathogens. One way to reduce this risk is to isolate sick individuals and indeed anecdotes from many different social animals tell of dying animals isolating themselves from their companions shortly before death. However, there is a lack of hard scientific evidence for this.

African pygmies
Humans do show some height variation among population, here a European with Pygmies at the beginning of the last Century. Scan of Collier's New Encyclopedia, Volume 1 (1921). Courtesy of Wikimedia Commons.
We might think that whereas most animals in the same species looks alike, we, humans, show a lot of individual variation. However, new research shows that in fact humans are much similar than we think. The scientists compared variation in length (height) and body mass in various human populations and compared it to animal populations. Surprisingly, they found that humans show some of the lowest levels of variation in height, whereas variation in body was around the average variation found in animals.

Hermit crabs exaggerate their fighting ability with misleading claw displays

Jane Palmer, Ph.D.

 

Hermit crab
Back off. Male hermit crabs display their claws to intimidate and deter attackers. Credit Hans Hillewaert by courtesy of Wikimedia Commons
Well-endowed hermit crabs are not shy about displaying their claws
Fourty meters in length, 17 meters height and 100 tons weight: the largest animals ever alive were the dinosaurs who reigned earth for more than 100 million years, twice as long as every other recent or fossil land vertebrate class. But why did no mammal ever reach that size of those giants of the primitive times? Palaeontologist Prof. Dr. Martin Sander and his collegue Dr. Marcus Clauss (University of Bonn, Germany) now give in a recent "Science"-paper a plausible explanation for the giantism of the sauropods: A bird like lung, laying eggs, a flexible metabolic rate and the lack of teeth allowed especially to the herbivores among the dinosaurs to get that big.