|
 Scientists said on Wednesday they reached that conclusion based on
the discovery of seven little teeth during excavations involving the
Panama Canal's expansion, showing monkeys had reached the North
American continent far earlier than previously known.
The teeth belonged to Panamacebus transitus, a previously unknown
medium-sized monkey species. South America at the time was secluded
from other continents, with a strange array of mammals evolving in
what 20th century American paleontologist George Gaylord Simpson
called "splendid isolation."
How Panamacebus performed the feat is a bit mysterious. After all,
seagoing simians seem somewhat suspicious.
 "Panama represents the southernmost extreme of the North American
continent at that time," said Jonathan Bloch, a vertebrate
paleontology curator at the Florida Museum of Natural History on the
University of Florida campus.
"It may have swum across, but this would have required covering a
distance of more than 100 miles, a difficult feat for sure. It's
more likely that it unintentionally rafted across on mats of
vegetation," Bloch added.
Bloch said as far as anyone knows these monkeys were the only
mammals that managed to cross the seaway from South America to reach
present-day Panama. While South American giant ground sloths managed
to reach North America about 9 million years ago, it was not until
about 3.5 million years ago that the Isthmus of Panama formed,
allowing animals to begin trekking in large numbers between the
continents in one of the biggest mixing of species on record.
Bloch said learning that monkeys lived then in North America was a
"mind-bending discovery" because it had long been accepted that they
simply did not exist there at that time.
[to top of second column] |
It would be akin to learning that Australia's kangaroos and koalas
live in the wilds of Asia today.
Monkeys originated in Africa and later spread to other parts of the
world. Scientists believe monkeys made an even lengthier
transoceanic voyage, perhaps 37 million years ago, when they
transited from Africa to South America, also probably on floating
debris.
Bloch said the seven teeth, the largest of which were molars about
one-fifth of an inch (5 mm) long, were unmistakable as belonging to
a South American monkey, and their shape showed Panamacebus had a
diet of fruit in its tropical forest environment.
The research was published in the journal Nature.
(Reporting by Will Dunham; Editing by Sandra Maler)
[© 2016 Thomson Reuters. All rights
reserved.]
Copyright 2016 Reuters. All rights reserved. This material may not be published,
broadcast, rewritten or redistributed.
 |
