News / Science & Technology

    Scientists Discover Crocodile Fossil with Mammalian Teeth

    When crocodiles tried to be mammals: the Cretaceous crocodilan /Pakasuchus kapilimai/, with a complete set of mammal-like teeth hunts dragonflies on an ancient Tanzanian floodplain
    When crocodiles tried to be mammals: the Cretaceous crocodilan /Pakasuchus kapilimai/, with a complete set of mammal-like teeth hunts dragonflies on an ancient Tanzanian floodplain
    Jessica Berman

    Scientists have unearthed the fossil of a crocodile-like animal in Africa that had mammal-like teeth, suggesting that the prehistoric creature could bite and chew its food - an ability modern crocodiles do not possess.  

    Paleontologists discovered the remains of the unique creature in a river bank in southwestern Tanzania, where they have dug up other fossils from the mid-Cretaceous period more than 100 million years ago.

    The ancient reptile was smaller than a house cat, its skull fitting easily in the palm of one's hand.  Bony plates ran down the tail and back, much like modern crocodiles.

    But researchers like Patrick O'Connor of Ohio University say the animal's most striking feature is its teeth.

    "If someone were just to describe those teeth, the shapes and how they interact with one another or work together, most people would read that as a very mammalian-like dental series," said Patrick O'Connor.

    O'Connor led the international team of paleontologists that found a complete specimen of the crocodilian reptile in 2008, and has since recovered portions of seven other creatures.

    O'Connor says the latest fossil find - an intact skull - includes sharp incisors at the front of its mouth for tearing food, and interlocking upper and lower molars at the back of the jaw that were used for grinding.  

    Modern crocodile teeth, by contrast, are of equal size and all are extremely sharp, according to Paul Filmer, program director of geology and paleobiology at the U.S. National Science Foundation, which co-funded the expedition with the National Geographic Society.

    "The crocodilians with which you and I are familiar have a very characteristic smile, as it were," said Paul Filmer. "The teeth or the dentition that they have is mainly a row of conical teeth which may vary a little bit in size and angle, but they're pretty much all the same and they basically serve that function which is [to] grab and tear."

    Scientists say modern crocodiles did not evolve from the prehistoric crocodile-like creature that was a species of ancient reptiles called notosuchians crocodyliform that died out around the same time that other land-dwelling dinosaurs became extinct.

    Paleontologists say notosuchians are characterized by a variety of different tooth structures and patterns.

    Researcher Patrick O'Connor says the 100-million-year-old reptiles, which flourished across a southern landmass the predated the African continent, probably filled a unique ecological niche.

    "Maybe there was a certain place in the ecology or in the environment where these animals lived that allowed them to experiment with the shape of the teeth," he said. "And as evolution works, if that was a successful experiment, then a group could go on and have a very long history."

    O'Connor says studying the notosuchians and their surprising dental features could help explain how modern crocodiles developed their sharp-toothed smile.

    An article describing the discovery of the reptilian fossil with mammalian teeth is published this week in the journal Nature.

    You May Like

    Clinton, Trump and the 'Woman’s Card'

    Ask supporters of Democratic front-runner in US presidential campaign, and they’ll tell you Republican presidential candidate is playing a dangerous hand

    Russian Censorship Group Seeks Chinese Help to Better Control Internet

    At recent Safe Internet League forum in Moscow, speakers from both nations underscored desire for authorities to further limit and control information online

    Video Makeshift Pakistani School Helps Slum Kids

    Free classes in Islamabad park serve a few of the country’s nearly 25 million out-of-school youths; NGO cites ‘education crisis’

    This forum has been closed.
    Comments
         
    There are no comments in this forum. Be first and add one

    Featured Videos

    Your JavaScript is turned off or you have an old version of Adobe's Flash Player. Get the latest Flash player.
    Turkish Kurd Islamist Rally Stokes Tensionsi
    X
    April 29, 2016 12:28 AM
    In a sign of the rising power of Islamists in Turkey, more than 100,000 people recently gathered in Diyarbakir, the main city in Turkey’s predominantly Kurdish southeast, to mark the birthday of the Prophet Muhammad. The gathering highlighted tensions with the pro-secular Kurdish nationalist movement. Dorian Jones reports from Diyarbakir.
    Video

    Video Turkish Kurd Islamist Rally Stokes Tensions

    In a sign of the rising power of Islamists in Turkey, more than 100,000 people recently gathered in Diyarbakir, the main city in Turkey’s predominantly Kurdish southeast, to mark the birthday of the Prophet Muhammad. The gathering highlighted tensions with the pro-secular Kurdish nationalist movement. Dorian Jones reports from Diyarbakir.
    Video

    Video Pakistani School Helps Slum Kids

    Master Mohammad Ayub runs a makeshift school in a public park in Islamabad. Thousands of poor children have benefited from his services over the years, but, as VOA's Ayesha Tanzeem reports, roughly 25 million school-age youths don't get an education in Pakistan.
    Video

    Video Florida’s Weeki Wachee ‘Mermaids’ Make a Splash

    Since 1947, ‘mermaids’ have fascinated tourists at central Florida’s Weeki Wachee Springs State Park with their fluid movements and synchronized ballet. Performing underwater has its challenges, including cold temperatures and a steady current, as VOA’s Lin Yang and Joseph Mok report.
    Video

    Video Somali, African Union Forces Face Resurgent Al-Shabab

    The Islamic State terror group claimed its first attack in Somalia earlier this week, though the claim has not been verified by forces on the ground. Meanwhile, al-Shabab militants have stepped up their attacks as Somalia prepares for elections later this year. Henry Ridgwell reports there are growing frustrations among Somalia’s Western backers over the country’s slow progress in forming its own armed forces to establish security after 25 years of chaos.
    Video

    Video Bangladesh Targeted Killings Spark Wave of Fear

    People in Bangladesh’s capital are expressing deep concern over the brutal attacks that have killed secular blogger, and most recently a gay rights activist and an employee of the U.S. embassy. Xulhaz Mannan, an embassy protocol officer and the editor of the country’s only gay and transgender magazine Roopban; and his friend Mehboob Rabbi Tanoy, a gay rights activist, were hacked to death by five attackers in Mannan’s Dhaka home earlier this month.
    Video

    Video Documentary Tells Tale of Chernobyl Returnees

    Ukraine this week is marking the 30th anniversary of the world's worst nuclear accident, at the Chernobyl nuclear power plant. Soviet officials at first said little about the accident, but later evacuated a 2,600-square-kilometer "exclusion zone." Some people, though, came back. American directors Holly Morris and Anne Bogart created a documentary about this faithful and brave community. VOA's Tetiana Kharchenko reports from New York on "The Babushkas of Chernobyl." Carol Pearson narrates.
    Video

    Video Nigerians Feel Bite of Buhari Economic Policy

    Despite the global drop in the price of oil, Nigerian President Muhammadu Buhari has refused to allow the country's currency to devalue, leading to a shortage of foreign exchange. Chris Stein reports from Lagos businessmen and consumers are feeling the impact as the country deals with a severe fuel shortage.
    Video

    Video  Return to the Wild

    There’s a growing trend in the United States to let old or underused golf courses revert back to nature. But as Erika Celeste reports from one parcel in Grafton, Ohio, converting 39 hectares of land back to green space is a lot more complicated than just not mowing the fairway.
    Video

    Video West Urges Unity in Libya as Migrant Numbers Soar

    The Italian government says a NATO-led mission aimed at stemming the flow of migrants from Libya to Europe could be up and running by July. There are concerns that the number of migrants could soar as the route through Greece and the Balkans remains blocked. Western powers say the political chaos in Libya is being exploited by people smugglers — and they are pressuring rival groups to come together under the new unity government. VOA's Henry Ridgwell reports.
    Video

    Video Russia’s TV Rain Swims Against Tide in Sea of Kremlin Propaganda

    Russia’s media freedoms have been gradually eroded under President Vladimir Putin as his government has increased state ownership, influence, and restrictions on critical reporting. Television, where most Russians get their news, has been the main target and is now almost completely state controlled. But in the Russian capital, TV Rain stands out as an island in a sea of Kremlin propaganda.

    Special Report

    Adrift The Invisible African Diaspora