For some species of worms, decapitation is not a big deal – they only grow up a new head.
But far from this superpower, which is an ancient skill, a recent study shows that this ability is relatively recent adaptation in
Regeneration is unusual in animals, but species that can do this are sprinkled throughout the animal kingdom and include sea stars, hydri, fish, frogs, salamanders and spiders, as well as worms. The restoration of body parts has long been considered an ancient feature, with different animals that traced the ability to a distant common ancestor, which probably arose hundreds of millions of years ago.
But for some species of sea worms, the ability to revive broken teeth and brains trace only 10 million to 15 million years ago – it became a much more recent adaptation than previously thought – scientists said.
The types of worms were documented by the growing heads and brain: four of them saw that they did it for the first time, which was previously known. for regeneration of the head. In addition, researchers found additional evidence in earlier studies of head growth in three more types of tapeworms. independently of only a few species of worms. It also raises important questions about all animals that can regenerate body parts, researchers wrote.
"When we compare groups of animals, we can not assume that the similarity in their regeneration ability is old and reflect the common origin," – co-author Alexander Bily, a biology associate at the University of Maryland, said in a statement