时间:2024-09-20 07:51:45 来源:网络整理编辑:熱點
The species of alligator roaming Florida's swamps and golf courses may be millions of years older th
The species of alligator roaming Florida's swamps and golf courses may be millions of years older than previously thought, scientists from the University of Florida said.
What's more, the sharp-toothed reptiles we see today may be almost biologically identical to their millennia-old ancestors -- an incredibly rare trait for most living species, according to a pair of studies shared with Mashablethis week.
"What we saw 8 million years ago in Florida is virtually the same thing as what we have there today," Evan Whiting, the studies' lead author and a vertebrate paleontologist, said by phone from Gainesville.
SEE ALSO:Greenland sharks could be the world's longest-living vertebratesWhiting and his research team compared the fossils of the American alligator (Alligator mississippiensis) with those of extinct alligator species. They found that the minute differences in each species' forms were instead just variations of the same singular species.
Greetings from your nightmares.Credit: RHONA WISE/AFP/Getty ImagesTheir findings extend the American alligator's lineage by about 6 million years, according to the study published in the Journal of Herpetology. Scientists had previously believed the species emerged about 2 million years ago, when the most recent Ice Age began.
"To hit this exact set of features in the American alligator, and for them to keep such a huge presence in the area that's now the Southeast U.S. for 7 to 8 million years, is nothing short of spectacular," Alex Hastings, the assistant curator of paleontology at the Virginia Museum of Natural History, told Mashable.
"The fact that their populations are doing pretty well today is a testament to their evolutionary success," said Hastings, who was not involved in the University of Florida studies.
The Florida researchers also found that, millions of years ago, American alligators shared the Florida peninsula with a species of 20-foot-long crocodiles, according to a separate study in the journal Palaeogeography, Palaeoclimatology, Palaeoecology.
While the crocs fed mostly on marine-based prey, the alligators stuck to freshwater or terrestrial sources -- a trait that still persists in American alligators, which lack the salt-secreting glands needed to thrive in saltwater.
The Alligator mississippiensis has proved resilient to naturally occurring changes in the climate and environment over millions of years. But in the modern era, the species' survival is increasingly at risk.
Map of the modern continental U.S. showing the rough geographic range of the American alligator.. Nebraska inset (top right) shows approximate localities for Alligator thomsoni (1) and Alligator mefferdi (2) fossils. Florida inset (bottom right) shows approximate localities for the Alligator olseni (3) fossils and the location of the Moss Acres Racetrack Alligator (4).Credit: journal of herpetology/"Cranial Polymorphism and Systematics of Miocene and Living Alligator in North America"Florida's booming population and sprawling real estate have steadily destroyed the alligators' habitat in recent decades. The reptiles landed on the U.S. endangered species list in the late 1960s, although the species was removed in the 1980s after the population recovered thanks to habitat protection efforts.
Encroaching on alligators' habitat has dangerous consequences for humans, as well. In June, an alligator killed a toddler visiting Walt Disney World in Orlando, marking the fourteenth deadly alligator attack in Florida since 2000.
Human-caused climate change poses another serious threat to the American alligator. Florida's low-lying landscape and porous bedrock make it particularly vulnerable to rising sea levels and saltwater intrusion, which could destroy the gators' freshwater dwellings along with homes and communities across the peninsula.
An American Alligator swims in Everglades National Park, Florida, on June 23, 2016.Credit: RHONA WISE/AFP/Getty Images"With increasing sea levels, we may see the available habitat for American alligators disappear," Whiting said.
As Florida sinks underwater and global temperatures warm, the alligator may move north over centuries to perhaps as far north as modern-day South Dakota and Nebraska, where Alligator mississippiensis likely originated.
"These things could be recolonizing parts of the United States that they haven't occupied in millions of years," Hastings said.
More than half of women in advertising have faced sexual harassment, report says2024-09-20 07:32
中超重慶隊2外援入選各自國家隊 期待兩人健康歸隊2024-09-20 07:27
穩!範迪克再將盧卡庫放進口袋 小魔獸威風不再2024-09-20 06:57
戰術板:藍軍長傳防反有聲有色 紅軍陣地進攻收效甚微2024-09-20 06:44
What brands need to know about virtual reality2024-09-20 06:29
張稀哲:國足尚未開始技戰術訓練 李鐵強調快節奏高對抗2024-09-20 06:08
28日賠率:阿森納難逃慘敗曼城 利物浦不勝切爾西2024-09-20 05:58
於無聲處聽驚雷 !巴薩新大腿神仙球 1對2華麗舞蹈2024-09-20 05:57
Whyd voice2024-09-20 05:39
傻傻分不清 !英超新援手指商標 誤當隊徽美滋滋2024-09-20 05:32
Daughter gives her 1002024-09-20 07:45
曼聯官宣C羅Ins獲1250萬+次點讚 創體育俱樂部曆史2024-09-20 07:44
沒梅西更不會踢!格刀比賽數據慘淡 遭巴薩球迷狂噓2024-09-20 07:41
厲害!德赫亞獻逆天神撲救主 曼聯兩代門神齊誇獎2024-09-20 07:29
Man stumbles upon his phone background in real life2024-09-20 06:53
轉會通 :尤文7000萬歐追C羅替身 阿森納還要再砸錢2024-09-20 06:43
熱刺前瞻:凱恩歸來狀態火熱 孫興慜迎6周年裏程碑2024-09-20 06:35
國足正式開啟戰術訓練 李鐵單獨與兩大隊長交流2024-09-20 06:34
Florida hurricane forecast remains uncertain, but trends in state's favor2024-09-20 05:43
比賽日:勒溫點射埃弗頓22024-09-20 05:13