Just when we thought we had these thing figured out. Intro of topic
Sharks are infamous meat-eaters. The ocean’s buffet of fish, crabs, mussels, shrimp and krill fill the legendary predators’ stomachs and give them sustenance. Now researchers have discovered that one particular species, bonnethead sharks, also dine on seagrass to meet their nutritional needs. The discovery means bonnethead sharks are not carnivores but omnivores — a distinction that changes how the coastal swimmers influence the fragile ecosystems they call home.
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That means these coastal sharks once thought to be solely meat-eaters are actually omnivorous and the only known shark species to eat plants. That distinction changes things for ecosystem managers since omnivorous fish are food web stabilizers. Roni Dengler, “These First-Known Omnivore Sharks Eat Seagrass” at Discover Magazine
Countless balances like that probably stabilize the ecology, while upsetting long-held assumptions about life forms.
See also: More resourceful than thought: Neanderthals on cold steppes also ate plants
Note: Some claim that Neanderthals did not eat plants and that’s why they died out: See: In the latest version, cold climate helped to do in the Neanderthals The thesis that Neanderthals did not adapt by eating plants or fish is, of course, vulnerable to the potential discovery of fish bones and plant offal in the remains of Neanderthal settlements. (Neanderthals need a cultural interpreter. )