This post highlights zoology-related articles which have featured in the news over the last two weeks.
Great white sharks (Carcharodon carcharias) in the Mediterranean Sea may be descended from Australian ancestors. Researchers publishing in Proceedings of the Royal Society B sequenced the mitochondrial control region of four Mediterranean great white sharks and found that their DNA was most similar to the DNA of sharks from Australia and New Zealand. The research team hypothesize that the ancestral sharks lost their way due to climatic oscillations during an interglacial period to create this new, isolated population. As the sharks always return to their place of birth to breed, this Mediterranean population is extremely vulnerable. Read the news articles on Nature News network, BBC News and the Telegraph.
Relative to their body size, barnacles have the largest penis in the animal kingdom. Now, researchers have found that acorn barnacles (Semibalanus balanoides) can vary the length of their penis depending on their surrounding environment. For example, barnacles located in sparsely populated neighborhoods have increased folds in the penis, allowing greater stretch to reach potential mates, while barnacles exposed to rough seas grow wider organs to withstand the waves. The research is published in Marine Biology and you can read the news article on the Discover Magazine blog, Discoblog.
The cleptoparasitic fly (Cacoxenus indagator) has an unusual mechanism for escaping from their hosts’ brood cells. Research published in Physiological Entomology describes how these flies inflate a blister on their head by pumping it full of hemolymph and then use the hydraulic pressure to break free. Read the news article on the New Scientist blog, Zoologger.
Large predators, such as tigers and polar bears, are particularly affected by environmental disturbance according to a study recently published in Biology Letters. Researchers looked at the influence of prey abundance on the predator density of 11 species of carnivores to find out why larger species are so highly threatened. Read the news article on the Telegraph.
by Anne Braae