Topic: Biology

Scientists studied humpback whales in the South Pacific and found that older males are more successful at fathering calves as populations recover from centuries of whaling. They used genetic testing to determine paternity and an 'epigenetic molecular clock' to estimate whale ages.

Whales were once on the brink of extinction due to commercial whaling, but conservation efforts have helped their numbers rebound. A new study published in Current Biology reveals that this recovery has led to a shift in who fathers the calves. Researchers from the University of St Andrews analyzed nearly 20 years of data from humpback whales breeding in the South Pacific waters around New Caledonia.

As whale populations grew, the age structure of breeding groups changed. Initially, younger males dominated, but as numbers increased, a more balanced mix of younger and older individuals emerged. This change led to older whales becoming more successful at fathering calves than their younger competitors.

The study used genetic testing to determine paternity and an 'epigenetic molecular clock' to estimate whale ages. These tools allowed scientists to analyze the data and draw conclusions about the changing behavior of male humpback whales.

Why It Matters

Understanding how whale populations recover can inform conservation efforts and help us better manage marine ecosystems. This research also highlights the importance of continued study on recovering species, as their behavior may be shaped by historical events like whaling.

Key Facts

• The study analyzed nearly 20 years of data from humpback whales breeding in the South Pacific waters around New Caledonia.
• As whale populations grew, older males became more successful at fathering calves than younger competitors.
• Researchers used genetic testing to determine paternity and an 'epigenetic molecular clock' to estimate whale ages.

Key Terms

Epigenetic molecular clock

A technique that estimates the age of individual whales by analyzing their DNA

Implications

Understanding how whale populations recover can inform conservation efforts and help us better manage marine ecosystems. This research also highlights the importance of continued study on recovering species, as their behavior may be shaped by historical events like whaling.