June 29 (UPI) -- Inbreeding makes animals more vulnerable to environmental changes, new research shows.
When scientists inbred beetles, they found the insects made poorer decisions as environmental factors changed.
In the lab, researchers observed the behavior of dozens of female burying beetles as they reared their young on the carcass of a dead mouse. In the middle of the experiment, scientists altered the beetles' food source, swapping out the first mouse carcass for a second smaller mouse carcass.
Beetles that were inbred failed to adapt, raising too many young despite the smaller food source. The control group, non-inbred beetles, culled portions of their larvae clutch, as the beetles do in the wild, ensuring all of their young are sufficiently fed.
The offspring of inbred beetles were born with lower body weights, diminishing their odds of survival and of mating and bearing offspring.
Researchers believe the poor planning by the inbred beetles is likely caused by impaired cognition or an inability to accurately sense their surroundings.
Previous research has shown inbreeding alone can reduce an animal's ability to or likelihood of successfully reproducing. The latest findings -- published this week in the journal Proceedings of the Royal Society B: Biological Sciences -- suggests environmental changes can compound the negative impacts of inbreeding.
"The impact of environmental conditions can amplify the effects of being inbred, such as susceptibility to disease or competing for resources," Jon Richardson, biological scientist at the University of Edinburgh, said in a news release. "We now know that poor decision-making plays a part in the burden facing inbred animals."