AIRLINK 217.98 Decreased By ▼ -4.91 (-2.2%)
BOP 10.93 Increased By ▲ 0.11 (1.02%)
CNERGY 7.55 Decreased By ▼ -0.01 (-0.13%)
FCCL 34.83 Decreased By ▼ -2.24 (-6.04%)
FFL 19.32 Increased By ▲ 0.08 (0.42%)
FLYNG 25.15 Decreased By ▼ -1.89 (-6.99%)
HUBC 131.09 Decreased By ▼ -1.55 (-1.17%)
HUMNL 14.56 Decreased By ▼ -0.17 (-1.15%)
KEL 5.18 Decreased By ▼ -0.22 (-4.07%)
KOSM 7.36 Decreased By ▼ -0.12 (-1.6%)
MLCF 45.63 Decreased By ▼ -2.55 (-5.29%)
OGDC 222.08 Decreased By ▼ -1.18 (-0.53%)
PACE 8.16 Decreased By ▼ -0.02 (-0.24%)
PAEL 44.19 Increased By ▲ 0.69 (1.59%)
PIAHCLA 17.69 Decreased By ▼ -0.37 (-2.05%)
PIBTL 8.97 Decreased By ▼ -0.10 (-1.1%)
POWERPS 12.51 Decreased By ▼ -0.50 (-3.84%)
PPL 193.01 Decreased By ▼ -5.23 (-2.64%)
PRL 43.17 Increased By ▲ 0.93 (2.2%)
PTC 26.63 Decreased By ▼ -0.76 (-2.77%)
SEARL 107.08 Decreased By ▼ -3.00 (-2.73%)
SILK 1.04 Decreased By ▼ -0.02 (-1.89%)
SSGC 45.00 Decreased By ▼ -2.30 (-4.86%)
SYM 21.19 Increased By ▲ 0.42 (2.02%)
TELE 10.15 Decreased By ▼ -0.37 (-3.52%)
TPLP 14.51 Decreased By ▼ -0.44 (-2.94%)
TRG 67.28 Decreased By ▼ -1.57 (-2.28%)
WAVESAPP 11.29 Decreased By ▼ -0.63 (-5.29%)
WTL 1.70 Decreased By ▼ -0.09 (-5.03%)
YOUW 4.25 Decreased By ▼ -0.10 (-2.3%)
BR100 12,397 Increased By 33.3 (0.27%)
BR30 37,347 Decreased By -871.2 (-2.28%)
KSE100 117,587 Increased By 467.3 (0.4%)
KSE30 37,065 Increased By 128 (0.35%)

WASHINGTON: Paleontologists have found a well-preserved fossil of a four-legged amphibious ancestor of whales, a discovery that sheds new light on the mammals' transition from land to the ocean.

The ancestors of whales and dolphins walked on Earth about 50 million years ago in the regions that now comprise India and Pakistan.

Paleontologists have previously found partial fossils of the species in North America that were 41.2 million years old suggesting that by this time, the cetaceans had lost the ability to carry their own weight and walk the Earth.

The new specimen, described in a study published Thursday in the journal Current Biology, is 42.6 million years old and provides fresh information on the evolution of cetaceans.

The fossil was found about 0.6 miles (one kilometer) inland from Peru's Pacific coast, at Playa Media Luna.

Its mandibles grazed the desert soil and during excavations, the researchers found the lower jaw, teeth, vertebrae, ribs, parts of front and back legs, and even the whale ancestor's long fingers that were likely webbed.

Based on its anatomy, the scientists say this cetacean of about 13 feet (four meters) long could both walk and swim.

"Part of the tail's vertebrae showed similarities with that of present-day semi-aquatic mammals like otters," lead author Olivier Lambert of the Royal Belgian Institute of Natural Sciences told AFP.

"This would therefore have been an animal that would have started to make growing use of its tail to swim, which differentiates it from older cetaceans in India and Pakistan."

Pieces of four-legged whales were found in Egypt, Nigeria, Togo, Senegal and Western Sahara, but they were so fragmented that it was impossible to decisively conclude whether they could swim.

"This is the most complete specimen ever found for a four-legged whale outside of India and Pakistan," said Lambert.

If the whale in Peru could swim like an otter, the researchers hypothesized that it likely crossed the Atlantic from the western coast of Africa to South America. As a result of continental drift, the distance was half that of today, around 800 miles, and the east-west current of the time would have facilitated their travel.

This finding would make less likely another hypothesis according to which whales reached North America via Greenland.

The Pisco Basin, off Peru's southern coast, likely holds numerous fossils, given its excellent conditions for preservation.

"We have work for at least the next 50 years," said Lambert, the paleontologist.

Copyright AFP (Agence France-Press), 2019
 

Comments

Comments are closed.