Wild animals provide a unique challenge for physiologists because they are difficult to capture and monitor in their natural habitats. As a result, scientists are increasingly learning about organisms ...

Human beings, fish, reptiles and birds have the same hormones in their blood with very similar functions. But why does one find hormone values in some species that are ten times higher than in others?

I probably don't need to tell you that, although they're among our most basic biological functions as human beings, conception and pregnancy are basically the closest any of us are ever going to get ...

When a Zoos Victoria team had difficulties breeding some of their critically endangered mountain pygmy-possums, they decided to investigate the animals’ hormone levels. A lot is known about hormones ...

Epaulette sharks reproduce effortlessly, without using much energy. The epaulette sharks, also known as “walking sharks,” do ...

A large-scale analysis of 117 mammal species found that preventing reproduction is associated with longer lifespans, suggesting a strong link between reproductive activity and life expectancy. Why do ...