The prevailing hypothesis concerning the evolution of the anthropoid visual system is that ancestral haplorhines were nocturnal. Later their descendants invaded a diurnal niche, with the evolution of highly acute, three-color vision. Now, a new study (Melin et al. 2013) challenges this view, suggesting instead that stem haplorhines already possessed three-color vision before they move into a fully diurnal niche.
Twitter limits human communication to a mere 140 characters. Animals’ scent posts may be equally as short, relatively speaking, yet they convey an encyclopedia of information about the animals that left them.
Within stable groups, leadership roles often go to dominant or experienced individuals. For example, elephant social groups are lead by a matriarch with years of experience and knowledge that presumably increases the survival of her followers. Likewise, packs of wolves are lead by a dominant alpha pair; subordinates are essentially forced to follow their lead.
A new study involving bat skulls, bite force measurements and scat samples collected by an international team of evolutionary biologists is helping to solve a nagging question of evolution: Why some groups of animals develop scores of different species over time while others evolve only a few. Their findings appear in the current issue of Proceedings of the Royal Society B: Biological Sciences.
It is difficult for humans to imagine that a world of color and sound exists outside of the one that we can perceive, but for some organisms that world is a reality. Usually these animals aren’t ones that we can readily relate to; bats and dolphins are two examples that both possess the ability to hear and emit high-frequency sounds. Continue reading Tarsiers — Communication in the Ultrasound