Why do taxonomy

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Gulf of Guinea Expeditions. Marine Exploration. Click here for information on the biography and legacy of the "father of taxonomy", Carl Linnaeus. What's in a Name? This reflects a real biological difference — a species is defined as a potentially interbreeding group of organisms that can produce viable offspring that themselves can interbreed.

Thus animals of two different species, like a horse and a zebra, cannot interbreed, while animals of the same species can. Taxonomists provide unique names for species, labels that can help us find out more about them, and enable us to be sure that we are all talking about the same thing. How to Name a Species: the Taxonomic Process 1 Taxonomists begin by sorting specimens to separate sets they believe represent species.

Over time, however, scientists found that crocodiles were more closely related to birds than either of them were to other reptiles. This was found first via morphological studies but later well-confirmed via molecular analysis, Baum said. This left taxonomists in a quandary about what the grouping "reptile" should refer to, as one of its core members was now seen to be more closely related to an outsider, Baum said.

Related: Are birds dinosaurs? Taxonomists could have reserved the term "reptile" for referring to the noncrocodile members snakes, lizards and turtles , as crocodiles were more closely related to birds. Instead, scientists expanded reptiles to now include birds.

Expanding even further, scientists eventually accepted that one group of dinosaurs, the theropods, are more closely related to birds than to any other reptiles. Evidence for this built over the years, beginning with the bird-like Archaeopteryx in the s and continuing through the discovery of many feathered dinosaurs in the s. Again, taxonomists could have restricted the term "dinosaurs" to those dinos from which birds didn't descend.

But researchers instead opted to maintain the grouping of all previously recognized dinosaurs , as Dinosauria, while acknowledging birds as the descendants of one dino branch. Related: What's the difference between alligators and crocodiles? By responding to evolutionary findings like this, taxonomy does more than change nomenclature: It helps scientists avoid errors, Baum said.

They tend to jump to false conclusions. Evolution hasn't always played this role in taxonomy, however. Today's hierarchical, ranked system originated with Charles Linnaeus, an 18th-century Swedish botanist. Linnaeus didn't subscribe to Darwin's theory — partly for the forgivable reason that it hadn't been invented yet. So the first huge milestone in modern taxonomy's own evolution, Baum said, came with the incorporation of evolutionary theory. Exactly how to do that, however, remained unclear until the mids.

Then, German scientists like Willi Hennig showed that "if you want to reflect evolutionary history, then you should only give names to … these groups that all come from a common ancestor," Baum said. Today, these "monophyletic groups," or groups that descend from a common ancestor, govern how taxonomists delineate taxa, with groups branching off the tree of life from their common ancestors.

That's why every genus in a family must share a common ancestor and so on. That's a monophyletic group. Other major events in taxonomy's own evolution served to reinforce the insights of Darwin and Hennig.

The advent of DNA analysis has helped scientists more accurately measure how related organisms are, and leaps in computational power have since accelerated those genetic discoveries, Baum said. But in the midst of this gleaming, modern computational era, taxonomy retains traces of its centuries-old roots — which some scientists, including Baum, refer to as baggage. The binomial names, for starters, grew from Linnaeus' pre-Darwinian mindset.

For Linnaeus, Baum said, "The genera were what God created, and after the creation, there were some rearrangements that happened to generate different species of the genus. So genus was the kind — 'genus' means 'kind' in Latin — [and] species were the variety, the modification of that. Thus, the very naming system that gives us Homo sapiens and Tyrannosaurus rex reflects a Creationist view, Baum said.