If you have a bird or birding question you'd like Kenn to answer, leave them in the comments below or on Facebook. Maybe next month you'll get the kind of thorough, thoughtful, and even humorous response from Kenn we've grown so fond of over the years. Kenn Kaufman: Once when I was an avid pre-teen birder, I got in a big argument over birds and words.
Anyone can look at the long-legged wading birds and see their wide variety of shapes, sizes, markings, and colors, making it obvious that they are not all the same thing. They represent many different species. But how closely related are they? That question has sparked a considerable amount of debate—not as noisy as my boyhood argument with my cousins, perhaps, but still intense—for many years. As scientists have developed better tools and methods for studying the relationships of living things, they have found that the wading birds separate out naturally into some very distinct groups.
The overall framework for how we classify birds has not changed much for a long time, and you may have memorized it in high school biology. The class Aves is divided into a number of orders of birds. Each order contains one or more families. Within each family there may be one genus or more plural: genera , and each genus includes one or more species.
Some intermediate categories are sometimes used, such as subfamily and subgenus. Although the framework of the classification has not changed much, the arrangement of various kinds of birds within the system has changed radically over time. All of the long-legged wading birds were once classified in the same order.
Now they are spread out across four separate orders, none of them particularly close to the others. Our modern system of classification and scientific names for birds and other animals dates back to , when Carolus Linnaeus published the 10th edition of his Systema Naturae.
Linnaeus was a brilliant innovator, but at that time, scientists had no good means of judging whether species were related, other than sheer superficial similarity. In fact, that order, which he called Grallae, also included the sandpipers, plovers, oystercatchers, rails, and even ostriches. Apparently, longish legs were practically the only qualification needed for membership in this group.
Cranes also have shorter beaks than herons. Flamingos can be friendly to humans, but only if they have been with humans for a long time. They can form long-lasting relationships with humans if trained correctly. Flamingos and shrimp are actually both pink from eating algae that contains carotenoid pigments. Flamingos eat both algae and shrimp-like critters, and both contribute to their fabulous pinkness.
While stronger chicks are not aggressive towards weaker siblings, as is the case in some species, weak or small chicks are sometimes killed by their parents.
This behaviour occurs in times of food shortage to reduce brood size and hence increase the chance of survival of the remaining nestlings. Actively scan device characteristics for identification. Use precise geolocation data. Select personalised content.
Create a personalised content profile. Measure ad performance. Select basic ads. There may be one or more plural: genera within each family, and each genera includes one or more species. Sometimes some intermediate categories are used, such as subfamily and subgenus.
But for a basic understanding of bird classification, it is sufficient to consider order, family, genus, and species. Although the classification framework has not changed much, over time, the arrangement of various birds in the system has undergone fundamental changes. All long-legged wading birds have been sorted in the same order. They are now distributed in four different commands, none of which are particularly close to the others.
Therefore, it is not surprising that Linnaeus classified flamingos, spoonbills, ibis, herons, storks, and cranes in the same order. In fact, this order he called Grallae also includes snipes, plovers, oysters, railroad tracks, and even ostriches. Obviously, long legs are actually the only condition for being a member of the group. It is interesting to look back at how Linnaeus grouped some birds in his original list. Shrike, Those predatory songbirds , In the same order as the owl, eagle, and falcon.
Ducks, puffins, thrushes, albatross, seagulls, and penguins all have an order. Among the long-legged waders of the Linnaean order Grallae, ibis and some long-billed sandpipers are grouped together.
This order not only includes cranes, they even Placed in the same genus As a great blue heron, this will undoubtedly please my controversial cousin.
At the time, structural similarity was seen as a sign of relevance. We now know that things like the shape of the beak and the length of the legs can easily evolve—of course, over a long period of time—to better adapt to certain food sources or eating behaviors. As a result, unrelated birds will eventually Form a similar shape. In fact, as we know, such things have happened many times in wading birds. Although the shape of the beak may be somewhat consistent in a family, the length of the legs does not really indicate anything useful for classification.
By the time The first bird list of the Federation of American Ornithologists AOU , published in , scientists began to look at the relationship of all these groups more critically. For example, they separated the flamingos in their own order. This is not surprising; if we look closely at flamingos, they are strange birds, and their brilliant colors are not their most unusual place. They wade in shallow water with incredibly long legs, lower their necks, and put their heads upside down in the water.
They open their mouths gently and use their fleshy tongues to draw water from the gaps. The small comb-like structures on the mandibles filter out food from the water: the smallest crustaceans, insects, mollusks, algae and other plankton.
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