Fish Arms



Look out, Nemo – there’s a shark on your tail!


This is Sandra Tsing Loh with the Loh Down on Science.


Undersea life can be brutal – one quick chomp, and a fish can lose a fin! But some lucky fish can grow them back, including bones: the fishy equivalent of arms and legs. Humans can’t do that!


Meet Igor Schneider and colleagues at the Federal University of Pará in Brazil. They study the genes of different types of fish with this superpower. They wondered – have different species  evolved different ways of restoring limbs?


By comparing their genes across species, the team found that different types of fish use the SAME sets of genes to grow limbs back. This suggests fish obtained this ability long BEFORE different species branched off.


Humans split off from fish ages ago. Surprisingly, we have many of these SAME genes in our DNA! We just lost the ability to use them! Understanding how fish turn these genes on or off could eventually bring us closer to re-growing a human arm.


Okay, my pet goldfish isn’t the smartest – but he has a fin-tastic secret power!