A new study has identified a squid that broods its eggs–an uncommon characteristic for an invertebrate.
Most invertebrates don’t provide any parental care for eggs or young, but the females of a squid species found in northern Japan do just that. They brood their eggs in their arms and presumably carry them around for months.
This behavior has been observed many times since the early 1990s, but, until now, the species remained a mystery. The study, led by a group of Japanese scientists, identified the squid as Gonatus madokai. This is the third squid species now known to brood.
In order to identify the species, the research team photographed and collected females, their eggs and their hatchlings and then analyzed tissue samples from two of the brooding females.
The length of the brooding period is unknown, “but the females presumably brood the eggs for at least several months,” John Bower, the study’s lead author, told MST.
During this period, she gets very weak. Bower explained that “the eggs presumably remain attached to six of the eight arms, which means the females cannot feed during the brooding period.”
It is still unclear why the females of these three species would spend so much time and energy on their eggs, but the authors suggest that it likely increases the fitness of her offspring by protecting them from predators and harsh conditions.
“More brooding squids await discovery, especially in the deep sea,” Bower said. Hopefully they will provide more clues to this fascinating behavior.
To learn more:
- Find the study, published in The Biological Bulletin, here: Brooding in a Gonatid Squid off Northern Japan
- And read about the cover image
Copyright © 2013 by Marine Science Today, a publication of Marine Science Today LLC.