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Neatly classifying living things into different species is a cornerstone of modern biology, but the criteria for distinguishing species are surprisingly fluid. On the whole, scientists have at least 16 Species definitionand potentially About 32 piecesIn general terms 2 million known species What exists today.
After all, that number is constantly changing as species are adjusted or reclassified based on new evidence. Single species are often split into several species, and seemingly different species sometimes turn out to be the same species.
From African elephants to killer whales, even seemingly popular and established animals have come under scrutiny. Here are six examples where scientists seem to have got them classified wrong.
Manta
For hundreds of years, manta rays were universally regarded as a single species, MantaThen, in 2009, Andrea Marshall, a graduate student at the University of Queensland, paper Manta rays are divided into two different species: the giant manta ray, or the oceanic manta ray (Mobra birostris) and a manta ray on the reef (Mobra AlfrediAt the time, Marshall suggested the possibility of a third species, and in 2020, researchers Published genetic evidence This supports her claim: The new species has yet to be formally described, but is colloquially known as the Caribbean manta ray.
Florida Panther
Deep in the Florida Everglades, you might be lucky enough to catch a glimpse of the state’s largest and most endangered cat, the Florida panther, which is smaller than the common cougar and has a curled tail that is believed to be the result of inbreeding among dwindling populations.
And this big cat has been a source of controversy since its discovery in 1896. Throughout the 19th and 20th centuries, scientists wavered over whether to classify the Florida panther as a type of North American puma or as some other species.Puma Concolor Cougar) and unique subspecies identification (P. c. coryiIn 2017, as part of a global effort to standardize the classification of the world’s felines, Cat Classification Task Force We chose the former and eliminated the entire population of pumas in North America. P. c. Cougar.
Reef Fish
Coral reefs are some of the most biodiverse habitats in the world. Everywhere they go, people live, and every crumb of food is eaten. This intense competition for space and resources forces species to diversify to find new niches. This phenomenon, called adaptive radiation, has given rise to thousands of new species, many of which look very different from one another. But in other cases, species are so similar that scientists can only tell them apart by looking at their DNA. This is a form of hidden biodiversity. study In a paper published in February, scientists found that the DNA of one species of tiny sponge-dwelling fish called a goby contains seven different gene lineages that could represent new species, the senior co-author said. Jordan CaseyMolecular ecologist at the University of Texas at Austin’s Marine Science Institute.
African Elephant
African elephants were once thought to be a single species. However, in 2021, it was discovered that African savannah elephants (or bush elephants) and African savannah elephants (African brown) and African forest elephant (Loxodonta cyclotis).
And the scientists Previously argued Splitting species into more and more groups can make it harder for conservationists to allocate resources, but the African elephant is one example where new data is actually making it easier. The International Union for Conservation of Nature (IUCN), the organization that manages the list of threatened species, previously listed one species of African elephant as endangered, but splitting the group means that it is no longer endangered. Reclassification of African forest elephants Its designation as a species seriously threatened with extinction paved the way for new conservation measures.
Due to a population decline of over 86% in the past 30 years, some populations It is now stable. This is due to strict anti-poaching policies.
Killer whale
Killer whales are a famous example of speciation occurring in real time. There are an estimated 50,000 killer whales. Killer whale The currently existing species is classified as one species, Orcinus orca,at least 10 different ecotypesEach has a unique appearance, behavior and habitat. For example, resident orcas have small ranges and are good at eating fish, while migratory orcas travel long distances and feed on seals and other whales. Now these populations have diverged enough that they struggle to communicate and reproduce with each other, leading some scientists to Pushing for reclassification That would split orcas into multiple species.
giraffe
When the famous Swedish biologist Carl Linnaeus first described the spindly, strange-looking giraffe in 1758, he I did this without actually seeing the animal.However, for hundreds of years, he classified giraffes as a single species (giraffe) survived. In 2016, when scientists had access to cutting-edge genetic tools, it became clear that the roughly 120,000 giraffes alive today are actually 4 different speciesTheir proposals were and still are controversial: for example, the IUCN continues to list the giraffe as a single species with nine subspecies.
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