Reproduksjon
Researchers at James Cook University have found that epaulette sharks, also known as walking sharks, lay eggs without any measurable rise in energy use, defying expectations for reproductive costs. The study tracked metabolism, blood, and hormones throughout the sharks' reproductive cycle, revealing remarkable stability. This efficiency could indicate resilience in changing ocean conditions.
Rapportert av AI
An international study of mammals in zoos shows that limiting reproduction through contraception or sterilization increases average lifespan by about 10 percent. The effects differ between sexes, with males benefiting from reduced testosterone and females from avoiding pregnancy's physical toll. These findings highlight a key evolutionary trade-off between breeding and survival.