Live fast, die young: study reveals why some birds mature quicker

Scientists have discovered the reason why some birds live fast, die young in findings that could help predict how animals will adapt to climate breakdown and habitat destruction.

Research from the University of Sheffield has revealed why some bird species take longer to develop than others. The study, published in Nature Communications, is the first to consider the importance of lifestyle, environment, evolutionary history and body size when explaining variation.

Size, safety and parenting all have an impact on how quickly a species of bird matures, according to the research. The scientists studied thousands of species to understand why there is so much diversity in the length of time they take to grow from a fertilised egg to an independent adult.

All organisms face a trade-off between reproducing and surviving and have adapted to solve this problem in different ways. The team found bird species with a “live fast, die young” strategy develop quicker, allowing them to maximise the number of offspring they can produce in the short time they have available.

Dr Chris Cooney, the study’s lead author, said: “The amount of time it takes for a fertilised egg to develop into a fully grown adult varies hugely across the animal kingdom. For instance, it takes an elephant almost 10 years to reach independence, whereas a fruit fly is fully grown after only a matter of days.

“This extraordinary diversity is also encapsulated within birds, where albatrosses can take almost a year to develop from an embryo to an independent adult, but a typical UK garden songbird takes little more than a month. We found that certain aspects of a species’ lifestyle and environment are important in explaining how long they take to develop.”

Findings showed birds that breed and live in safer environments with fewer predators typically took longer to develop, possibly because they can afford to spend longer in a vulnerable state.

They also found that migratory birds develop much more quickly, which may ensure they are ready to return to their winter habitats at the end of the summer.

As expected, the research showed bigger birds took longer to develop – but even among birds of a similar size there was variation in development times.

Dr Nicola Hemmings, a co-senior author of the research, said the insights could prove crucial in understanding and even predicting how organisms may respond when conditions change, “for instance as our climate warms and habitats become modified”.