Animals May Evolve Much Faster Than Previously Thought

Started by stromboli, December 16, 2015, 10:39:45 AM

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stromboli

http://www.huffingtonpost.com/entry/animals-evolution_5670cda0e4b0688701db8554

Animals Are Evolving Faster Than You Think And There Is Proof

QuoteBiological evolution, the changes in living organisms over time, is often considered an elusive and long process that cannot be observed during a human lifespan. But is that really the case? And is there evidence that we can see it happening right before our eyes?
Evolution is a process that occurs at a different pace in different organisms. For instance, paleontologists have shown, thanks to the fossil record, that it took a million years for whales to evolve from their land-dwelling mammalian ancestors.
But evolution can also be observed and monitored in living organisms within a human lifetime. This is true for infectious agents, such as bacteria and parasites, that can evolve extremely quickly to resist the drugs we use to fight them. But it is also the case for larger organisms, such as vertebrates â€" the back-boned animals.

One of the most famous examples was documented in a population of finches living on Daphne Major island in the Galapagos archipelago. In this case, ground finches Geospiza fortis evolved larger beaks after a major drought in 1977. During this harsh period, the small seeds on which the ground finches were feeding on became scarcer, and most of the birds died.
However, scientists noticed that the mortality rate was lower among larger birds, with a larger beak. They were able to crush bigger and harder seeds to feed on while the small seeds were depleted. Large-beaked finches had a great advantage over their small-beaked relatives to survive these tough conditions. They reproduced more and transmitted this trait to their offspring. Following the drought, scientists observed a shift towards larger beaks and body size among subsequent generations.
Strikingly, researchers reported a reversal towards small body and beak size after large rain falls and abundant small seed supply in 1983. Monitoring the finch population over the years has thus allowed scientists to observe their rapid evolution and to link it to different environmental changes.

The fact that evolution can be rapid not only allows scientists to observe it in action, it also means that they can perform real-time experiments in the field to test their hypotheses by changing specific environmental parameters.
Recently, a team of scientists in Florida demonstrated that rapid evolution of a species can be triggered by a negative interaction with a competitor. To do so, the scientists introduced an invasive species of anole lizard to a group of small islands that shared the same lifestyle and diet as the native one, Anolis carolinensis.

The invader anoles forced the native ones to move from their original habitat on the forest floor and into the trees. Scientists were not only able to follow the rapid shift in the lifestyle of the native anole species (they perch higher and higher in the trees over time), but also observed that it involved rapid changes to their body shape. Within only 15 years (20 generations), the native anole species evolved larger toe pads with stickier scales, enabling them to climb more efficiently in their new, higher habitat.

Closer to home, many invertebrates change quickly, too. Bed bugs, for example, have rapidly evolved in the last few decades, developing tougher exoskeletons to protect them from the insecticides and other poisons in their increasingly urban environment.
In his On the Origin of Species, Darwin considered evolution as a very slow process, the outcome of which would have taken much more time than an human lifespan. Of course, Darwin’s assumption was making sense of things in the scientific context of his epoch, but the field observations and experiments conducted over the past 40 years have shown that animals often evolve very rapidly indeed. Life, it seems, never stays still.

The creationist argument is that we have not seen actual Speciation or change sufficient to declare that a known species has evolved into a new species, despite evidence of the mechanism involved. But Darwin's model of adaptation in any respect is well proven, and there are numerous instances of changes within species such as bacteria and other infectious agents. The current problem with antibiotic resistant diseases is a very good example.

Mr.Obvious

Curious to see how christian-scientists will implement this one to 'prove' god done did it.
I'm sure they will. Just curious towards the how.
"If we have to go down, we go down together!"
- Your mum, last night, requesting 69.

Atheist Mantis does not pray.

Gawdzilla Sama

Tell the creationists to try to cross breed chihuahuas and Great Danes. It's just like breeding a Smart car to a semi-tractor/trailer rig. Ain't gonna happen. And humans did that!
We 'new atheists' have a reputation for being militant, but make no mistake  we didn't start this war. If you want to place blame put it on the the religious zealots who have been poisoning the minds of the  young for a long long time."
PZ Myers

Baruch

G-d of the gaps ... science of the gaps.  You can't prove that macro-evolution works, unless you are prepared for a million year controlled experiment.  Micro-evolution clearly works.  Paleontology strongly suggests that macro-evolution works too.  The species question is a red herring ... there are no species ... a tiger and a lion can be cross-bread ... but yet they seem to be different species to me, not different varieties of the same species (Bengal vs Snow tigers).  So seeing "speciation" happen in real time, even will million year time-lapse photography, won't happen, because you can't tell when you shift from one species to the next.

The Galapagos are a clear exception to the rule ... species variation happens more quickly there.  But off Madagascar, the coelacanth  hasn't changed in 100 million years.
Ha’át’íísh baa naniná?
Azee’ Å,a’ish nanídį́į́h?
Táadoo ánít’iní.
What are you doing?
Are you taking any medications?
Don't do that.

Gawdzilla Sama

Micro-evolution and macro-evolution are just evolution. An almost imperceptible change in a creature is the "micro" end. All of that creature being gone and a different creature evolving out of it is the "macro" end.
We 'new atheists' have a reputation for being militant, but make no mistake  we didn't start this war. If you want to place blame put it on the the religious zealots who have been poisoning the minds of the  young for a long long time."
PZ Myers

Gawdzilla Sama

BTW, nothing happens in the Galapagos that can't happen elsewhere. There's nothing "magic" about the place.
We 'new atheists' have a reputation for being militant, but make no mistake  we didn't start this war. If you want to place blame put it on the the religious zealots who have been poisoning the minds of the  young for a long long time."
PZ Myers

stromboli

http://evolutionlist.blogspot.com/2009/02/macroevolution-examples-and-evidence.html

QuoteWhile studying the genetics of the evening primrose, Oenothera lamarckiana, de Vries (1905) found an unusual variant among his plants. Oenothera lamarckiana has a chromosome number of 2N = 14. The variant had a chromosome number of 2N = 28. He found that he was unable to breed this variant with Oenothera lamarckiana. He named this new species Oenothera gigas.

Digby (1912) crossed the primrose species Primula verticillata and Primula floribunda to produce a sterile hybrid. Polyploidization occurred in a few of these plants to produce fertile offspring. The new species was named Primula kewensis. Newton and Pellew (1929) note that spontaneous hybrids of Primula verticillata and Primula floribunda set tetraploid seed on at least three occasions. These happened in 1905, 1923 and 1926.


We are looking for speciation and macroevolution in higher life forms. But the same argument holds true for any life form at any stage; if speciation can be seen at the bacterial level, it can therefore be argued it occurs in higher life forms. In the case of the Galapagos, what you are talking about is an isolated set of ecosystems not acted upon from outside sources, hence a fairly unique environment. But as Gawd pointed out, it can definitely happen elsewhere.

Micro environments have been discovered in rain forests. A section of a waterfall in the Amazon forest was found to be so enclosed because of cliffs and surrounding geology that it presented an area not affected by any outside force, other than the water of the fall.


Gawdzilla Sama

If you want macroevolution, the wolf and the pug are there for you.
We 'new atheists' have a reputation for being militant, but make no mistake  we didn't start this war. If you want to place blame put it on the the religious zealots who have been poisoning the minds of the  young for a long long time."
PZ Myers

Hydra009

Quote from: Baruch on December 16, 2015, 01:00:05 PMYou can't prove that macro-evolution works, unless you are prepared for a million year controlled experiment.
http://www.talkorigins.org/indexcc/CB/CB901.html



You're right that we can't perform a million-year experiment.  But we don't need to.  We can examine ancient taxa that strongly resemble modern taxa on both a morphological and genetic level, which in turn, strongly resemble even more ancient taxa, etc.  Absent a magician waving a magic wand and summoning these taxa from the ether, the conclusion of common descent is pretty much inescapable.

stromboli


Baruch

#10
Quote from: Gawdzilla Sama on December 16, 2015, 01:16:33 PM
BTW, nothing happens in the Galapagos that can't happen elsewhere. There's nothing "magic" about the place.

I didn't realize you had giant tortoises and sea iquanas in your yard ;-)

Pretty pictures of pretty reconstructions of fossils that were at best partial?  Well that is what paleontology does.  But until we get Jurassic Park, we really don't know much.

My major point is that ... species is a category people invented, like race ... it doesn't exist in nature ... living things are a continuum, that only appear to be individuals.  But we can't think or talk about it like that, so we have to invent convenient categories.
Ha’át’íísh baa naniná?
Azee’ Å,a’ish nanídį́į́h?
Táadoo ánít’iní.
What are you doing?
Are you taking any medications?
Don't do that.

stromboli

http://www.talkorigins.org/indexcc/CB/CB910.html

QuoteNew species have arisen in historical times. For example:

A new species of mosquito, isolated in London's Underground, has speciated from Culex pipiens (Byrne and Nichols 1999; Nuttall 1998).

Helacyton gartleri is the HeLa cell culture, which evolved from a human cervical carcinoma in 1951
. The culture grows indefinitely and has become widespread (Van Valen and Maiorana 1991).

A similar event appears to have happened with dogs relatively recently. Sticker's sarcoma, or canine transmissible venereal tumor, is caused by an organism genetically independent from its hosts but derived from a wolf or dog tumor (Zimmer 2006; Murgia et al. 2006).

Several new species of plants have arisen via polyploidy (when the chromosome count multiplies by two or more) (de Wet 1971). One example is Primula kewensis (Newton and Pellew 1929).

Incipient speciation, where two subspecies interbreed rarely or with only little success, is common. Here are just a few examples:

Rhagoletis pomonella, the apple maggot fly, is undergoing sympatric speciation. Its native host in North America is Hawthorn (Crataegus spp.), but in the mid-1800s, a new population formed on introduced domestic apples (Malus pumila). The two races are kept partially isolated by natural selection (Filchak et al. 2000).
The mosquito Anopheles gambiae shows incipient speciation between its populations in northwestern and southeastern Africa (Fanello et al. 2003; Lehmann et al. 2003).
Silverside fish show incipient speciation between marine and estuarine populations (Beheregaray and Sunnucks 2001).

Ring species show the process of speciation in action. In ring species, the species is distributed more or less in a line, such as around the base of a mountain range. Each population is able to breed with its neighboring population, but the populations at the two ends are not able to interbreed. (In a true ring species, those two end populations are adjacent to each other, completing the ring.) Examples of ring species are

the salamander Ensatina, with seven different subspecies on the west coast of the United States. They form a ring around California's central valley. At the south end, adjacent subspecies klauberi and eschscholtzi do not interbreed (Brown n.d.; Wake 1997).
greenish warblers (Phylloscopus trochiloides), around the Himalayas. Their behavioral and genetic characteristics change gradually, starting from central Siberia, extending around the Himalayas, and back again, so two forms of the songbird coexist but do not interbreed in that part of their range (Irwin et al. 2001; Whitehouse 2001; Irwin et al. 2005).
the deer mouse (Peromyces maniculatus), with over fifty subspecies in North America.
many species of birds, including Parus major and P. minor, Halcyon chloris, Zosterops, Lalage, Pernis, the Larus argentatus group, and Phylloscopus trochiloides (Mayr 1942, 182-183).
the American bee Hoplitis (Alcidamea) producta (Mayr 1963, 510).
the subterranean mole rat, Spalax ehrenbergi (Nevo 1999).

Evidence of speciation occurs in the form of organisms that exist only in environments that did not exist a few hundreds or thousands of years ago.
For example:
In several Canadian lakes, which originated in the last 10,000 years following the last ice age, stickleback fish have diversified into separate species for shallow and deep water (Schilthuizen 2001, 146-151).

Cichlids in Lake Malawi and Lake Victoria have diversified into hundreds of species
. Parts of Lake Malawi which originated in the nineteenth century have species indigenous to those parts (Schilthuizen 2001, 166-176).

A Mimulus species adapted for soils high in copper exists only on the tailings of a copper mine that did not exist before 1859 (Macnair 1989).

There is further evidence that speciation can be caused by infection with a symbiont. A Wolbachia bacterium infects and causes postmating reproductive isolation between the wasps Nasonia vitripennis and N. giraulti (Bordenstein and Werren 1997).


Gawdzilla Sama

Quote from: Baruch on December 16, 2015, 07:04:28 PM
I didn't realize you had giant tortoises and sea iquanas in your yard ;-)

Pretty pictures of pretty reconstructions of fossils that were at best partial?  Well that is what paleontology does.  But until we get Jurassic Park, we really don't know much.

My major point is that ... species is a category people invented, like race ... it doesn't exist in nature ... living things are a continuum, that only appear to be individuals.  But we can't think or talk about it like that, so we have to invent convenient categories.
Is there a coherent version of this available online?
We 'new atheists' have a reputation for being militant, but make no mistake  we didn't start this war. If you want to place blame put it on the the religious zealots who have been poisoning the minds of the  young for a long long time."
PZ Myers

Gawdzilla Sama

We 'new atheists' have a reputation for being militant, but make no mistake  we didn't start this war. If you want to place blame put it on the the religious zealots who have been poisoning the minds of the  young for a long long time."
PZ Myers

Baruch

Quote from: Gawdzilla Sama on December 17, 2015, 01:45:12 AM
Is there a coherent version of this available online?

Look at time vs space ... you are a continuation of your parents ... your individuality is relative.  Without them (at least in the past), you don't exist.  These connections go all the way back past the Cambrian.  Looking outside of time, the tree of life is one organism.  This is similar to the bush in the Mohave, which sends long lived tendrils under ground, to spawn additional above ground expressions of itself ... but it is one plant, that covers many acres.  We are one being in the process of becoming ... though consciousness isn't present in all its parts (at least as we understand it) and consciousness is local (at least as we understand it).  It is as if your individual fingers were conscious of themselves and each other as separate, and the palm of the hand lay in the past, not horizontally.
Ha’át’íísh baa naniná?
Azee’ Å,a’ish nanídį́į́h?
Táadoo ánít’iní.
What are you doing?
Are you taking any medications?
Don't do that.