The skull of a 17 million-year-old whale provided clues for when in history geographical uplift occurred in East Africa.
The fossil represents the most precisely-dated beaked whale in the world that was found extremely far inland, Southern Methodist University reported. The findings provides insight into when East Africa's mysterious elevation started to progress.The whale was identified as a Turkana ziphiid, and most likely lived in the open ocean. The species is related to the modern beaked whale, which is still one of the ocean's top predators.
"The whale was stranded up river at a time when east Africa was at sea level and was covered with forest and jungle," said vertebrate paleontologist Louis L. Jacobs, Southern Methodist University. "As that part of the continent rose up, that caused the climate to become drier and drier. So over millions of years, forest gave way to grasslands. Primates evolved to adapt to grasslands and dry country. And that's when -- in human evolution -- the primates started to walk upright."
The whale is believed to have gotten disoriented and swam into the Anza River, which flowed in a southeastward direction into the Indian Ocean. Once it entered the rive it was not able to change its course, forcing it to swim further inland.
The researchers noted that determining ancient land elevation is difficult, but the whale demonstrates one near sea level.
The findings were published in a recent edition of the Proceedings of the National Academy of Sciences. Funding for the research came from SMU's Institute for the Study of Earth and Man and the SMU Engaged Learning program.
