Apparently, it helps jellyfish colonize new habitats via jellyfish “blooms” of masses of offspring, which they then eat:
Lead author of the study, Jamileh Javidpour, Assistant Prof. at University of Southern Denmark states “we combined a study of the population dynamics of this species with experimental feeding and geochemical tracers to show, for the first time, that adult jellies were actually consuming the blooms of their own offspring.”
This rather sinister realization behind the function of these blooms makes perfect sense. As a handy floating nutrient reservoir that lasted beyond the collapse of normal prey populations, the release of offspring provided adults with an additional 2-3 weeks window of growth which, ecologically, can be the difference between life and death.
“In some ways, the whole jelly population is acting as a single organism, with the younger groups supporting the adults through times of nutrient stress,” says Thomas Larsen, a co-author of the study at the Max Planck Institute for the Science of Human History.
University of Southern Denmark, “Cannibalism helps invading invertebrates survive severe conditions” at ScienceDaily
Well, if the whole colony is acting as a single organism to eat offspring and live, what becomes of the individual selfish gene? Oh, never mind. The heresy consists in even wondering.
“Because comb jellies trace their ancestry back to the beginning of most animal life as we know it during the Cambrian Period, 525 Million Years Ago, it remains possible that it is a basic, unifying feature across the animal kingdom,” Jamileh Javidpour concludes.
More research is certainly required to clarify the role of cannibalism among the earliest members of the animal kingdom and the evolutionary origins of cannibalism and the reasons why it is particularly prominent in aquatic ecosystems.
University of Southern Denmark, “Cannibalism helps invading invertebrates survive severe conditions” at ScienceDaily
Sell your stock in the selfish gene. But then, what is really happening here?
Paper. (open access)
For whatever reason, some of us were reminded of Roger Kimball, in his Introduction to the second edition (2006) of philosopher David (1927-1994) Stove’s Darwinian Fairytales (Encounter Books, 2006). He, and especially Stove, expertly skewer this type of thing. From Kimball:
He is particularly good at exposing the “amazingly arrogant habit of Darwinians” of “blaming the fact, instead of blaming their theory” when they encounter contrary biological facts. Doctrinaire Darwinists have an answer for everything, always a bad sign in science, since it means that mere facts can never prove them wrong. Does it regularly happen that increasing prosperity leads to lower birth rates? And does this directly contradict Darwinian theory? No problem, just announce that the birth rates in such cases are somehow “inverted,” evidence of a “biological mistake.”
Kimball writes very carefully, as a man who wants to avoid any association with the taint of imagining that there is some kind of design in nature. But his point is: No matter what the state of affairs, a gimcrack Darwinian explanation is always available.
Increasingly, it is held in place via the threat of career ruin.
At what point does that become a cost to genuine advance in the discipline?