"Nothing in biology makes sense except in the light of evolution" --Christian biologist Theodosius Dobzhansky Jun 11
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People who doubt evolution tend to have one main argument: "If evolution is true, why do we still see monkeys running around today, all chimp-like? Where are all the monkey-men I was promised ?" Well, if you or someone you know refuses to believe that organisms change over time without proof on a monkey-man level, here are a buttload of animals in the middle of getting their evolve on.
This is very cool ! I heard about the similarities but I've never seen it so well depicted ! by Jul 21
Humanity's track record with animals has never been stellar. After centuries of ocean dumping, worldwide deforestation, domestication and overhunting, it's safe to say we've got a greasy, opposable thumb in every one of Mother Nature's pies. That's not to say that humanity's only effect on the animal kingdom is pure destruction; in fact, sometimes our ecological footprint looks more like a clown shoe.
A raccoon baculum . The baculum (also penis bone , penile bone or os penis ) is a bone found in the penis of most placental mammals . It is absent in humans , but present in other primates , such as the gorilla and chimpanzee .
The archaeocetes are a paraphyletic group of primitive cetaceans that include the earliest, terrestrial 'whales'. The group consists of six families: Pakicetidae , Ambulocetidae , Remingtonocetidae , Protocetidae , Basilosauridae and Dorudontidae , although some scientists include the latter two in one single family Basilosauridae. The graph below shows, how these families are related to each other.
Semelparity and iteroparity refer to the reproductive strategy of an organism.
Vertebrate wings are homologous as forelimbs, being derived from the same organs; however, as organs of flight in pterosaurs (1), bats (2) and birds (3) they are analogous ; they resemble each other in some ways, and they fulfil similar functions, but their roles in flight have evolved separately. In biology, an analogy is a trait or an organ that appears similar in two unrelated organisms.
How many protons, electrons and neutrons are in an atom of krypton, carbon, oxygen, neon, silver, gold, etc...? To find the number of protons , electrons and neutrons in an atom, just follow these easy steps:
Early embryos of various species display some ancestral feature, like the tail on this human fetus . These features normally disappear in later development, but it may not happen if the animal has an atavism. [ 1 ] Atavism is the tendency to revert to ancestral type. In biology, an atavism is an evolutionary throwback, such as traits reappearing which had disappeared generations before. [ 2 ] Atavisms can occur in several ways.
Mimicry Some animals and plants look like other things -- they mimic them. Mimicry is another type of deceptive coloration.
Anaerobic bacteria are organisms that are capable of surviving and growing in an atmosphere of little or no oxygen.
The human race has scaled the tallest mountains, charted the deepest oceans and played a quick front nine on the freaking moon, but there's one frontier that still largely mystifies us: our own bodies. There are everyday phenomenons you'd think must have been explained ages ago, but in reality asking these simple questions of a scientist will net you at best a shrug, and at worst some bullshit he just made up off the top of his head. The act of yawning is baffling to experts for two reasons. One, it doesn't actually seem to serve any purpose. Seriously, when you feel a yawn coming on, suppress it.
Genetic drift or allelic drift is the change in the frequency of a gene variant ( allele ) in a population due to random sampling . [ 1 ] The alleles in the offspring are a sample of those in the parents, and chance has a role in determining whether a given individual survives and reproduces. A population's allele frequency is the fraction of the copies of one gene that share a particular form. [ 2 ] Genetic drift may cause gene variants to disappear completely and thereby reduce genetic variation . When there are few copies of an allele, the effect of genetic drift is larger, and when there are many copies the effect is smaller.
First thing you need to know: Before doing anything else, you should simply click “play” and start watching the video above. It doesn’t take long for Robert Sapolsky , one of Stanford’s finest teachers, to pull you right into his course. Better to watch him than listen to me. Second thing to know: Sapolsky is a MacArthur Fellow, a world renowned neurobiologist, and an adept science writer best known for his book, Why Zebras Don’t Get Ulcers . Much of his research focuses on the interplay between the mind and body (how biology affects the mind, and the mind, the body), and that relationship lies at the heart of this course called “Human Behavioral Biology.” Now the third: Human Behavioral Biology is available on YouTube and iTunes for free.
Thanks to the know-it-all from second grade, we're all aware that dolphins and whales are mammals, not fish. But it's probably been a while since you've pondered just how incredibly, mind-blowingly weird it is that you and whales were the same animal more recently than whales and sharks. Or to put it in chart form, you and whales split up somewhere in the big tangle of bio diversity up top labeled "Age of Mammals" while whales and fish haven't been the same animals since way the hell down ...