The over 3-foot-long marine predator sat at the top of Earth's first food chain, say scientists from the South Australian Museum and the University of Adelaide. They found fossils for the crustacean, named Anomalocaris, at Kangaroo Island, South Australia.
The University of New England's John Paterson, who led the study, and his colleagues explain that Anomalocaris held the #1 spot in the earliest food chain due to its large body size, formidable grasping claws at the front of its head, and a circular mouth with razor-sharp serrations.
Three-feet-long might not seem like that much, but consider the size of other marine animals then. We're talking about some of the world's first animals, after about 100 million years or so of evolution. The oceans included, as they do today, unicellular microscopic organisms as well as creatures like the 1.5-foot-long Hurdia.
The eyesight of Anomalocaris, now understood thanks to the recent fossil discovery, proves that this marine dweller had superb vision to support its predator lifestyle near what is now Kangaroo Island. The site dates to 515 million years ago, so it's possible the bug-eyed hunter goes back even earlier in time.
The fossils represent compound eyes. These are the multi-faceted kind seen in arthropods, such as flies, crabs and kin. They are perhaps the largest of their kind to have ever existed, with each eye over 1 inch in length and containing over 16,000 lenses.
The number of lenses and other aspects of their optical design suggest that Anomalocaris would have seen its world with exceptional clarity while hunting in well-lit waters. Only a few arthropods, such as modern predatory dragonflies, have similar resolution.
Read more at Discovery News
No comments:
Post a Comment