A nearly - complete frame of an ancient , elephantine , extremely toothy mahimahi has been found in South Carolina . The findings , release in the journalCurrent Biology , line an enormous mahimahi that was 4.6 metre ( 15 foot ) long and last in the Oligocene around 25 million year ago .
Previously only known to science from a fond podium ( the dolphin ’s snoot),Ankylorhiza tiedemani’stooth and flipper syllable structure reveal that this large - jagged whale ( from the genus Odontoceti ) was an solar apex marauder in the Oligocene sea . The remarkable discovery was that the animal ’s skeleton share significant similarities with modernistic jaggy and baleen whales , indicating that these animals shared a convergent evolution because they dwell similar aquatic environments .
" The level to which baleen hulk and dolphins independently arrive at the same overall swimming adaptations , rather than these traits evolving once in the common ancestor of both groups , surprise us , " said Robert Boessenecker of the College of Charleston in Charleston , South Carolina , in astatement . " Some examples admit the narrowing of the tail stock , increase in the number of tush vertebra , and shortening of the humerus ( upper sleeve bone ) in the fin .
" This is not apparent in different lineages of cachet and ocean lions , for example , which evolved into unlike modes of swimming and have very dissimilar looking postcranial skeletons , " he summate . " It ’s as if the addition of extra finger’s breadth bone in the flipper and the lockup of the human elbow joint has wedge both major group of cetaceans down a similar evolutionary pathway in terms of locomotion . "
The first partial frame ofAnkylorhizawas discovered in the 1970s by Albert Sanders , once a Charleston Museum Natural History curator . It was n’t until the late 1990s that scientists finally start out their hands on a full skeleton , which was air to the Mace Brown Museum of Natural History .
Amazingly , the research worker submit that the fossil evidence indicates that these mega dolphins were the top predators of the time , feasting on large prey , including killer hulk . They also say that the remains imply thatAnkylorhizawas the first echolocating cetacean to become an peak predatory animal . It was n’t until after this sinewy vulture was wipe out that sperm hulk and shark - toothed dolphins start to expand , though there was a gap of about 5 million age .
" Whales and dolphins have a complicated and long evolutionary story , and at a coup d’oeil , you may not get that imprint from forward-looking mintage , " Boessenecker said . " The fossil record has really cracked open this farsighted , winding evolutionary path , and fossil likeAnkylorhizahelp illuminate how this encounter . "
