Holy Yog-Sothoth, what have I missed? As for the rest of you lazy toads, step up to the plate!
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While there is plenty of current, visible evidence for Micro-Evolution, there is no current evidence or fossil evidence for Macro-Evolution. There are fossils for now-extinct species but none for any in-between stages; none at all! If Macro-Evolution were real then there would be millions.
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This is the favourite lie of the creationists, do not be taken in so easily. All species are transitional forms between their immediate ancestral species and their immediate descendant species, if they have any. They are also always whole organisms in and of themselves. You will never accept any evidence for evolution if you hold onto erroneous notions about it.
But to hammer the point in, I will submit examples of fossil specimens representing the transition from one major group of organisms to another. Deep breath. And here we go!
Odontochelys, a transitional turtle from the Triassic. Dorsal side:
Notice the teeth in the beak, something that modern turtles lack. The back is also odd, for a turtle. The ribs are flattened, but there's no shell.
Flip it over, this is the ventral side of another specimen.
Can you see the plastron (belly armour)? Here we have a long-legged, toothed reptile with a turtle's plastron and hints in the spine and ribs of the carapace to be. It also fits in perfectly with the evidence from embryology: baby turtles always grow the plastron before the carapace. This is something only scientific theories do: it predicts what evidence we will find in the future, and here we have specimens that fit into that prediction perfectly. Powerful evidence for evolution.
Yanocodon, a primitive Mesozoic mammal. It represents transition morphology from the reptilian jaw and ear to the mammalian jaw and ear. The mammalian earbones are descended from bones still found in reptilian jaws.
There is too much background information to condense to explain this specimen, but it can be found
here.
Najash rionegrina, a Cretaceous snake with legs.
This specimen supports the hypothesis that snakes are derived from a terrestrial origin, rather than a marine origin which is also debated. This is where it fits in the snake's cladistic tree:
The result is expressed in a strict consensus of two equally parsimonious trees (tree length of 270 steps,
ensemble consistency index of 0.526, and retention index of 0.654). Bremer support and bootstrap percentages are given
in the nodes (see Methods and Supplementary Information). Reconstructions of the pelvis and hindlimb elements of Najash,
Pachyrhachis and a boine snake are illustrated for comparison., the most recently discovered tetrapodomorph fish which has sparked the search for more fish-tetrapod intermediates in Australia.
Pectoral fin:
The fun thing about cladistic trees is that they also list transitional specimens without me having to type them all out.
Ah, good old
Tiktaalik roseae, the previously discovered tetrapodomorph, found in Devonian rock in Greenland.
It has a more mobile skull/neck than a fish, and its fin-like limbs clearly presage the digits of tetrapods.
The limbs alone have had whole papers dedicated to them.
Tiktaalik was definitely not a terrestrial animal, but with its muscular, bony limbs and strong pelvic girdle it could prop itself up on the substrate, perhaps even holding itself up out of the water. Its jointed digits could extend and splay out when pressed against the ground, increasing the surface area of limb contact. You can easily imagine it inhabiting shallow swamps and rivers where other, traditional large fish could not swim.
Wikipedia entry on Transitional Fossils
I'm going to take a break from listing species there for a moment. I could not possibly list them all at any rate: I only have so many years in me.
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Also, there's the simple question of two distinct genders of the same species to evolve completely seperate from one another and yet able to breed together.
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You win the Ray Comfort award for mind-blowing ignorance. Ray Comfort, notorious potatoes-for-brains, recently wrote on his blog:
Darwin theorized that mankind (both male and female) evolved alongside each other over millions of years, both reproducing after their own kind before the ability to physically have sex evolved. They did this through "asexuality" ("without sexual desire or activity or lacking any apparent sex or sex organs"). Each of them split in half ("Asexual organisms reproduce by fission (splitting in half)."
This unbelievable mockery of human intelligence is one of many on his site, which I will not subject you to here. I couldn't help but spy the striking similarity between what you and he said, but I am sure you did not mean what Comfy was on about.
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Our reproductive process alone is simply insanely, incredibly complex and sad to say, school syllabuses and scientific debaters really tend to leave out the complexities of our bodies when arguing for evolution.
If Macro-Evolution were true, we'd not even have reached the level of slime. We'd still be dust.
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Ours is more complex and less complex than many other species. You will find That the evolution of reproductive strategies and reproductive systems have left their mark through the tree of life too. Such as the
mammalian vagina, for which I have the merry benefit of an evolutionary article.
I feel I must also reach everyone here about the impact of retroviruses on evolution. Retroviruses reverse-transcribe their RNA into DNA and implant it into the genome of the infected cell, and if it is a germ cell (one that produces the gametes), it could be inherited by the offspring. And so they are. These are called Endogenous Retroviruses (ERVs) and the chance of the same strain of virus infecting exactly the same position in the genome more than once is significantly large enough to be confidently ruled out. These have clearly been passed down to us all from our common ancestors. Actually, some are suspected of involvement in certain auto-immune diseases, included multiple sclerosis- we are suffering from diseases that our ancestors contracted.
However, when we look at the great apes, we see that they share many of the same ERVs in exactly the same positions. Chimpanzees and bonobos share the most with us, followed by gorillas, the orangutans, other apes, monkeys etc, reflecting the same evolutionary relationship predicted by other aspects of the theory of evolution. There is no way to reasonably explain this phenomenon without common ancestry.
During pregnancy in viviparous mammals, ERVs are activated and produced in large numbers during the implantation of the embryo. They act as immunodepressors, protecting the embryo from its mother's immune system. Other viral proteins produces in this way fuse and cause the formation of the placental syncytium, preventing cells from migrating between the mother and embryo (a standard epithelium will not suffice, since some white blood cells are able to pass between epithelial cells. The ERV is similar to HIV, and functions in almost exactly the same way: it suppresses the immune system, causes cells to fuse with infected ones instead of infecting them individually etc. It appears that an ancient virus infected the ancestors of viviparous mammals, and the assimilation and subsequent employment of the virus' genes allowed for the evolution of viviparous reproduction, giving animals a way to gestate an organism inside themselves safe from the mother's immune system, whereas before an egg was required.
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Just so you know, if this sparks a big debate, I fear I will be flooded out, and I'm sorry if that happens.
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En garde.
Maybe the thread title built it up a bit too much,but the content is interesting I feel
