Roehampton lecturer explains reasons why wild animals die in The Biologist

  • Friday, April 27, 2018

Dr Lewis Halsey from the Department of Life Sciences explains the four main reasons for why wild animals die in an article for The Biologist, the journal for the Royal Society of Biology

In the article, Dr Halsey explains ‘Biologists instinctively focus on how animals live, not on how they die. Death is a main cog in the machine that drives evolutionary change. Death is central to biology’. 

Dr Halsey argues that, in order to better understand wild animals' lives, biologists must more thoroughly study death. Dr Halsey proposes four main categories of mortality: predation (which a high influence on mortality rates in cheetah cubs and deer), disease, misadventure (for example, extreme weather and loss of shelter) and starvation (most emperor penguin chicks die because they do not receive enough food). He goes on to argue that there are five ‘pathways to mortality’ that combine an ultimate and a proximate cause of death. For example, an animal may die from predation (proximate cause) because it was too weak from starvation or disease (ultimate causes) to escape or fight off predators. Dr Halsey concludes that low energy uptake is the single biggest driver of mortality in animals, as it is either the proximate or ultimate cause in most of these five pathways to death.

He proposes numerous avenues for future research, pointing out that for many animal species, the key causes of death have never been documented.

Dr Halsey said ‘We need a better understanding of the factors which lead to an animal's death. For many species, the main causes of death are simply undocumented. This blind spot is a huge problem when we are pursuing a better understanding of an animal's behaviour’.

To read the article entitled ‘A matter of life and… energy’, please click here.

The Department of Life Sciences at the University of Roehampton offers outstanding undergraduate courses in Zoology and Biological Sciences.