Latest news with #MolecularPhylogeneticsandEvolution
Yahoo
05-05-2025
- Science
- Yahoo
Scientists Found 2 New Crocodile Species Hiding in Plain Sight
Scientists know of four New World crocodile species, but a new study highlights potential fifth and sixth additions to the reptilian family. The two new crocodile species are each endemic to an island off the coast of the Yucatán—the tourist hotspot Cozumel and the atoll Banco Chinchorro. Although stable, the populations are small and are immensely vulnerable to habitat destruction. Of the estimated 8.7 million animal species on Earth, only 1.2 million of them have been officially described, with around 18,000 new species being discovered every year. Many of those are new kinds of jumping spiders, worms, insects, and other wriggling arthropods—the most abundant phylum in the animal kingdom. Huge reptiles don't typically make the list. However, a team of scientists from Canada, Mexico, and Panama claims they've discovered two previously unknown crocodile species off the Yucatán coast in a new study. With the four known species of New World crocodiles—the American, Morelet's, Cuban, and Orinoco—the addition of these two crocodile species discovered on Cozumel and the atoll Banco Chinchorro brings that number up to six. The details of these new species can be found in a new article published in the journal Molecular Phylogenetics and Evolution. 'Biodiversity is disappearing faster than we can discover what we're losing,' McGill biologist Hans Larsson, the senior author of the study, said in a press statement. 'Most species of crocodiles are already endangered, and rapid shoreline development threatens nearly every population. Our research aimed to uncover the true diversity of crocodiles on these isolated islands.' One of the oldest-living species of reptile on Earth—sharing (along with birds) some of its genetic lineage with the long-extinct dinosaur—crocodiles migrated to the Americas roughly seven million years ago during the tail end of the Miocene epoch. It's likely that a descendent of New World crocodiles, Crocodylus checchiai, traversed the Atlantic aided in part by westward ocean currents. Although well-known for its perplexingly slow rate of evolution, the crocodile eventually diversified into the four—now six—species we know today in the Americas. The discovery of these new crocs was completely unexpected, according to the study's lead author José Avila-Cervantes. Avila-Cervantes and his team compared the genetic sequences of the crocodile populations found on Cozumel and Banco Chinchorro to other known populations of New World crocodiles, and found enough genetic differentiation to necessitate a new species distinction—not just a variant of the American crocodile, the most widespread of the New World crocodiles. Scientific names have yet to be assigned to these new species, though a hat-tip to their respective island habitats seems like a good bet. Although it's always thrilling to discover a new species—especially one as large as these crocs—the study also adds a dash of concern. Although both populations are stable, they're small, in both ecosystem size and breeding population. The study estimates that each species contain fewer than 1,000 breeding individuals. 'Now that we recognize these crocodiles as distinct species, it's crucial to protect their habitats,' Larsson said in a press statement. 'Limiting land development and implementing careful conservation strategies on Cozumel and Banco Chinchorro will be key to ensuring their survival.' That could prove difficult, as both islands are popular tourist destinations. Cozumel has already seen more than 1.5 million cruise ship tourists in the first three months of 2025, which puts a strain not only on endemic species like crocodiles, but on natural wonders like the island's coral reef system. If the Cozumel and Banco Chinchorro crocodiles have any hope of survival, it'll be because the people of those islands recognize their undeniable worth to the surrounding ecosystem—the natural resource that brings millions flocking to these islands in the first place. You Might Also Like Can Apple Cider Vinegar Lead to Weight Loss? Bobbi Brown Shares Her Top Face-Transforming Makeup Tips for Women Over 50
Express Tribune
02-05-2025
- Science
- Express Tribune
Two new crocodile species discovered, scientists say
Listen to article Scientists have identified two previously unknown crocodile species off Mexico's Yucatán Peninsula, both of which may already be at risk of extinction due to small population sizes and habitat pressures. The new species were found on Cozumel Island and Banco Chinchorro, a coral atoll, and are genetically distinct from the American crocodile (Crocodylus acutus), according to a study published in the journal Molecular Phylogenetics and Evolution. The discovery brings the total number of known New World crocodile species to six. Until now, scientists recognised only the American, Morelet's, Cuban, and Orinoco crocodiles in the region. Researchers from Canada's McGill University, along with partners in Mexico and Panama, conducted genetic and anatomical analyses that revealed enough variation to classify the Cozumel and Banco Chinchorro populations as separate species. 'These results were totally unexpected,' said lead author José Avila-Cervantes. 'We assumed Crocodylus acutus was a single species ranging from Baja California to Venezuela and across the Caribbean.' The research involved collecting DNA and skull measurements from crocodiles in both locations. Notable differences included skull shape, with Banco Chinchorro crocodiles displaying longer and broader snouts. The study estimates that each new species has fewer than 1,000 breeding individuals, and effective population sizes may be as low as 500. While current numbers appear stable, scientists warned that limited habitat and increasing tourism-related development could pose serious risks. 'Biodiversity is disappearing faster than we can discover what we're losing,' said senior author Hans Larsson of McGill. 'Most crocodile species are already endangered. Protecting these habitats is critical.' Cozumel, a major cruise destination, received over 1.5 million visitors in the first three months of 2025 alone. Banco Chinchorro, part of the Mesoamerican Barrier Reef System, is also under ecological strain. The researchers urged governments and conservation groups to implement stricter land-use policies and establish habitat protections to preserve the newly identified species. Although the reptiles are yet to be formally named, researchers hinted that references to their geographic isolation—such as Crocodylus cozumelus or chinchorri—may be used in their taxonomic classification. The study highlights how natural barriers such as ocean currents in the Yucatán region have helped shape biodiversity by isolating species and allowing unique evolution to occur. 'These crocodiles are evolutionary survivors,' said Larsson. 'Now that we know they exist, we must ensure they don't disappear before they are even named.'
Yahoo
01-05-2025
- Science
- Yahoo
Scientists Found Two New Crocodile Species. They Were Hiding in Plain Sight.
Scientists know of four New World crocodile species, but a new study highlights potential fifth and sixth additions to the reptilian family. The two new crocodile species are each endemic to an island off the coast of the Yucatán—the tourist hotspot Cozumel and the atoll Banco Chinchorro. Although stable, the populations are small and are immensely vulnerable to habitat destruction. Of the estimated 8.7 million animal species on Earth, only 1.2 million of them have been officially described, with around 18,000 new species being discovered every year. Many of those are new kinds of jumping spiders, worms, insects, and other wriggling arthropods—the most abundant phylum in the animal kingdom. Huge reptiles don't typically make the list. However, a team of scientists from Canada, Mexico, and Panama claims they've discovered two previously unknown crocodile species off the Yucatán coast in a new study. With the four known species of New World crocodiles—the American, Morelet's, Cuban, and Orinoco—the addition of these two crocodile species discovered on Cozumel and the atoll Banco Chinchorro brings that number up to six. The details of these new species can be found in a new article published in the journal Molecular Phylogenetics and Evolution. 'Biodiversity is disappearing faster than we can discover what we're losing,' McGill biologist Hans Larsson, the senior author of the study, said in a press statement. 'Most species of crocodiles are already endangered, and rapid shoreline development threatens nearly every population. Our research aimed to uncover the true diversity of crocodiles on these isolated islands.' One of the oldest-living species of reptile on Earth—sharing (along with birds) some of its genetic lineage with the long-extinct dinosaur—crocodiles migrated to the Americas roughly seven million years ago during the tail end of the Miocene epoch. It's likely that a descendent of New World crocodiles, Crocodylus checchiai, traversed the Atlantic aided in part by westward ocean currents. Although well-known for its perplexingly slow rate of evolution, the crocodile eventually diversified into the four—now six—species we know today in the Americas. The discovery of these new crocs was completely unexpected, according to the study's lead author José Avila-Cervantes. Avila-Cervantes and his team compared the genetic sequences of the crocodile populations found on Cozumel and Banco Chinchorro to other known populations of New World crocodiles, and found enough genetic differentiation to necessitate a new species distinction—not just a variant of the American crocodile, the most widespread of the New World crocodiles. Scientific names have yet to be assigned to these new species, though a hat-tip to their respective island habitats seems like a good bet. Although it's always thrilling to discover a new species—especially one as large as these crocs—the study also adds a dash of concern. Although both populations are stable, they're small, in both ecosystem size and breeding population. The study estimates that each species contain fewer than 1,000 breeding individuals. 'Now that we recognize these crocodiles as distinct species, it's crucial to protect their habitats,' Larsson said in a press statement. 'Limiting land development and implementing careful conservation strategies on Cozumel and Banco Chinchorro will be key to ensuring their survival.' That could prove difficult, as both islands are popular tourist destinations. Cozumel has already seen more than 1.5 million cruise ship tourists in the first three months of 2025, which puts a strain not only on endemic species like crocodiles, but on natural wonders like the island's coral reef system. If the Cozumel and Banco Chinchorro crocodiles have any hope of survival, it'll be because the people of those islands recognize their undeniable worth to the surrounding ecosystem—the natural resource that brings millions flocking to these islands in the first place. You Might Also Like The Do's and Don'ts of Using Painter's Tape The Best Portable BBQ Grills for Cooking Anywhere Can a Smart Watch Prolong Your Life?
The Independent
29-04-2025
- Science
- The Independent
Two new crocodile species discovered in Caribbean – but they are already facing extinction
The discovery, reported in a new study published in the journal Molecular Phylogenetics and Evolution, sheds further light on the true diversity of American crocodiles and underscores the need for urgent conservation efforts to protect them. "Biodiversity is disappearing faster than we can discover what we are losing," Hans Larsson, a co-author of the study from Canada's McGill University, said. "Most species of crocodiles are already endangered, and rapid shoreline development threatens nearly every population.' The Americas are home to four species of Neotropical crocodiles of the genus Crocodylus. These species live in the warm, tropical regions of the continents, inhabiting coastal, inland and insular locations. They are a distinct group which evolved from ancestors that dispersed from Africa to the Americas around 5 million years ago. However, much of the evolutionary history of Neotropical crocodiles remains elusive. In the new study, researchers assessed the genetic sequences of crocodile populations from the Mexican island of Cozumel and the Banco Chinchorro atoll reef and compared these to crocodiles found across the Caribbean, Central America and on Mexico's Pacific coast. They found striking genetic differences in the sampled populations, leading them to conclude that the reptiles from Cozumel and Banco Chinchorro were not simply variants of the American crocodile Crocodylus acutus, but different species. The two new species also showed physical differences between themselves. 'The main differences between the populations are length and width of the skull,' the study noted. Banco Chinchorro crocodiles were characterised by a relatively long and broad snout compared to those on Cozumel. 'Our analysis supports Banco Chinchorro and Cozumel as genetically unique isolated populations,' researchers wrote, calling the results 'totally unexpected'. "We assumed Crocodylus acutus was a single species ranging from Baja California to Venezuela and across the Caribbean. Our study is the first to extensively explore genomic and anatomical variation in these animals,' said José Avila-Cervantes, another author of the study. The newly identified species were found to live in isolated populations of fewer than 1,000 breeding individuals, sparking concerns about their future. 'Estimated effective population sizes are only in the order of five hundred individuals in each population,' the study noted. Although their populations appeared stable, researchers warned that limited numbers and habitat restrictions left them vulnerable. "The rapid loss of biodiversity can only be slowed if we know what species are most at risk," Dr Larsson said. "Now that we recognise these crocodiles as distinct species, it's crucial to protect their habitats. Limiting land development and implementing careful conservation strategies on Cozumel and Banco Chinchorro will be key to ensuring their survival.'
