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34

Birds are both flying dinosaurs and flying reptiles. Yes, that's potentially confusing. To understand the apparent contradiction, you have to understand how modern classification of organisms works (phylogenetic systematics). Under the old (Linnean) classification system, Reptilia (reptiles) was an order and Aves (birds) was a separate order. Phylogenetic ...


21

The joint you are thinking (I assume) of is not a knee, nor is it an elbow, instead it is an ankle which is bending the same way as us humans. You can see from the below diagram that the knee - the joint between the femur and tibia - is just further up the leg normally hidden by feathers. Birds have a comparatively elongated metatarsus which gives the ...


16

Almost definitely (I'm not a regular birder) European Green Woodpecker (latin name: Picus viridis) and it is native to your area according to its species distribution map. "Green woodpeckers are the largest and most colourful woodpeckers native to Britain. They are easily recognised by their laughing ‘yaffle’ call, which they use to demarcate their ...


16

In addition to kmm's excellent answer, I'd like to present the xkcd point of view.


16

Birds have a body part known as the nicitating membrane otherwise known as the "third eyelid". This part has become vestigial in humans, where it remains as the plica semilunaris. This image of a masked lapwing clearly shows its nicitating membrane in action, where it covers the eye in a horizontal motion. This is analogous to blinking in humans, and the ...


14

The male kakapo (Strigops habroptila) in that video is called Sirocco. Kakapo were (and still are) very close to extinction, so in the 1980s the Kakapo Recovery Programme was launched. As part of this programme, rangers monitor all known kakapo in the wild, visiting their nests and generally ensuring they are in good health. When Sirocco was a young chick, a ...


14

I looked up winglets so I had context for this answer. I'm interpreting winglets as the vertical tips at the end of airplane wings. If so, then you are correct. The spread primary feathers of soaring birds like eagles function as winglets (Tucker 1993). Airbus has a biomimicry web page devoted to some of the biological designs, including winglets, they ...


12

The hoatzin has a digestive system that makes use of bacterial fermentation. Many other birds also consume grass, e.g. ostriches, ducks and geese. There's also a large body of literature on how birds can digest cellulose.


12

Flying came first, as far as we know. The earliest known bird (currently), Archaeopteryx lithographica, already had aerodynamic feathers (Feduccia and Tordoff, 1979). The Solnhofen Limestone, where it was discovered, is ~145 million years old, so we can place the "when" flight evolved to greater than or equal to that time. Gansus yumenensis is regarded as ...


12

Various features of brain,skull and beak anatomy help to achieve protection. A paper was published in PLoSOne in 2011 on this very topic: Why do woodpeckers resist head impact injury: a biomechanical investigation There is also a very readable summary on the BBC website. I advise that you read the whole article, but here is a quotation which lists the ...


11

This looks pretty much like a female zebra finch to me (the male have a more prominent feather pattern). See this picture: These birds are not native in Europe, this is correct. But it is always possible that birds escape captivity (or are released) and the live in countries where they originally not belong. I think this is the case with the zebra finch ...


10

Crows are omnivorous, and will eat almost anything they find or can kill. In this case the prey looks like a Yellow-Shafted Flicker.


10

This is a Cattle Egret (Bubulcus ibis), which is a heron in its breeding plumage. When not breeding, the bird is white. See the images for comparision: Breeding cattle egret with colored feathers. Nonbreeding cattle egret, completely white.


9

In mammals there are only two species (known, there may well be others) where males lactate. They are both species of bats and this paper discusses the evolutionary mechanisms that could underlie male lactation. I have ignored human cases because they are more of an unusual occurrence (often brought on by severe dietary stress) rather than an evolved ...


9

The logical assertion "winglets have not happened in a long time, therefore they are not advantageous" is incorrect. It is possible for an advantageous trait not to evolve even when advantageous, if there is no "path" to it. The trait only occurs gradually, in small incremental steps. If intermediary steps are harmful, the trait will not occur, even if the ...


8

LG stands for "linkage group". It seems the Chicken Genome Sequence group (Hillier et al., 2004) allocated several linkage groups (alleles or genes which tend to be inherited together) to the microchromosomes (tiny chromosomes typical of birds and reptiles), in this case called "linkage group E64" and "linkage group E22....". There are a load more ...


8

Definitions of adaptation Unfortunately, there is not such thing as a single, standard definition of adaptation. But for most cases the accurate definition the author is using is not of much importance as all of the usual definitions totally fit in the sentence without changing the meaning of the concept they want to express. In you case however, the ...


8

Most species of birds have 2 foveas, the temporal fovea and the central fovea. temporal fovea, which is like ours in the sense that it looks straight ahead and offers binocular vision (i.e. the temporal foveas of both eyes point in the same direction). But birds also have a central fovea, which points sideways and is, obviously, monocular (i.e., ...


8

There are two possibilites with evolutionary processes: The development either never went into this direction or it brought no advantages. Besides this two possibilities the claims from the other forum are wrong. Birds (not all of them though) do have winglet-like structures. If you look at big birds, you can see feathers on the end of the wings looking like ...


7

I'm not really inside the field but few weeks ago I noticed a Plos One article that was dealing with this. Indeed albatross can fly for thousands of miles and this is possible at no mechanical cost, because they use a dynamic way of flight that takes the energy from wind (dynamic soaring) (ref-1). Their muscle-skeletal system further evolved so that no ...


7

All animals develop in this way, whether they are oviparous (developing in an egg) or viviparous (developing inside their mother, or live-birth). From Wild Birds Unlimited: All mammals have navels or belly buttons where the umbilical cord distributes nutrients between a mother and her fetus. After birth, the umbilical cord is cut and a scar develops ...


7

Obviously, as you point out, some birds, such as waterbirds (ducks, puffins, auks, sandpipers) are perfectly fine in the rain, as they spend much of their time in the water anyhow and have oil glands that waterproof their feathers. For other birds, rain can increase heat loss. For instance, rain increases metabolism by up to 22% in eagles (Stalmaster & ...


7

I don't know of studies specifically of boat-tailed grackle flight, so I'll focus on elongated tails in general and come back to grackles at the end. Long tails in birds are obviously interesting from the standpoint of sexual selection. Going all the way back to Darwin, one hypothesis has been that females prefer males with long tails. There seems to be ...


6

This resource provides a short list of which general components of plumage are good indicators of a healthy bird. Your pet's plumage should be. . . Soft - feathers should be strong, yet flexible. Smooth - no rough feather shafts; no uneven or split edges Glossy - sheen extends over the entire coat Full - thick, where it needs to be ...


6

Hmmmm... the only one I can think of fitting at least in part your description would be the golden oriole (Oriolus oriolus). I say partly because it definitely is not 2-3 times a blackbird, could be slightly bigger, but on average it is the same size. Also it sounds extremely unlikely that you have spotted it in early March in Zurich, as they should be in ...


6

It looks like a passerine bird, but I can't really tell the species without seeing the whole body. As for what to do with it, your best course of action is to leave it alone. Trust me. Once placed tissue paper over a pigeon's eggs to keep them warm, and the mother crushed them when she landed on the nest because she didn't see the eggs. If there are eggs in ...


6

I confirm GriffinEvo answer: it is a Picus viridis. Additionally we can see it is a young male (immature). Young because the spots; picture of an adult here and young here. Male because the red spot under the cheeks, the females get this part only black.


6

It's the same stuff that makes up most sea shells, calcium carbonate, $CaCO_3$. Incidentally, this explains why egg shells dissolve in vinegar (acetic acid which, since it is an acid, provides the Hydrogen ions in the reaction below): $CaCO_3+ 2H^+ -> Ca^{2+} + H_2O +CO_2$ This simple reaction (which is what would happen in your stomach as well) ...


6

This is a pond heron or paddy bird. The de-facto source for identifying Indian birds is Birds of the Indian Subcontinent by Richard Grimmett, Carol Inskipp and Tim Inskipp. The book is remarkably complete and contains the vast majority of species found in the Indian Subcontinent.


6

I bet you'll be interested about the concept monophyly. Any human-made group of species (or taxon) like birds dinosaurs, primate, bacteria, angiosperm, reptiles, … are either monophyletic, polyphyletic or paraphyletic. This picture explain the concept When the taxon is monophyletic it is called a clade. Monophyletic taxon are those groups of species that ...



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