The starfish who couldn't say its age
one. The crown-of-thorns starfish is one of the most destructive coral predators in the Indo-Pacific, and until now no one could reliably say how old one is. There are no rings to count, no ear stones to read, no record at all. It eats for years and never says when it started.
two. The Australian Institute of Marine Science and James Cook University read its DNA instead. Across five age groups they found 1,910 spots where a chemical mark settles as the animal grows older. A model learned the pattern. Its average miss: about four months.
three. On a creature that lives five to eight years, four months is a season. Enough to tell one year's starfish from another's, which matters for managing an outbreak: home-grown, or new arrivals?
four. Then they shrank the clock to fourteen spots. Fourteen marks on a strand of DNA, and a predator that never kept a birthday suddenly has one. Kwong and colleagues, Biology Letters, 2026. PMID 42710879.
Sources: Kwong et al., Biology Letters (2026). doi:10.1098/rsbl.2026.0265 · PubMed 42710879
If there's a true thing you want told small, say the word: first chapter free, $20 if it lands.