Speedy toads advance theory of evolution

Mar 23, 2011
Professor Rick Shine: "This new process of evolution does not depend on survival or reproduction."

(PhysOrg.com) -- Speed and the mating habits of the Australian cane toad are set to expand the theory of evolution according to research published in the Proceedings of the National Academy of Sciences of the USA.

Three Australian biologists, including lead author, Professor Rick Shine, from the University of Sydney's School of Biological Sciences, believe they have identified a new evolutionary process based on their invasive cane toad research.

Professor Shine said the process, which depends on "mating between the quickest" rather than "survival of the fittest", challenges the long-held view that natural selection is the only driving force for evolution.

"For over 150 years, biologists have believed that is caused by only two factors: survival and reproduction," says Shine.

"This new process of evolution does not depend on survival or reproduction.

"In the leading-edge of a spreading population, such as an invasive pest, evolution can happen simply because the fastest individuals always end up at the invasion front.

"Repeated breeding between these fast-dispersing animals causes genes for rapid dispersal to become more and more concentrated in that zone."

Dubbed "spatial sorting", the new evolutionary process explains why the invasion of the - a highly poisonous tropical frog - has been accelerating through Australia for the last 70 years.

The seven-year study has shown that at the invasion front have evolved to move faster than those in areas colonised many years ago. The researchers, including Dr. Greg Brown, also from the School of Biological Sciences, and Dr. Ben Phillips from James Cook University believe this process provides a new explanation for why pest species spread faster over time.

Professor Shine says: "The toad's Australian invasion can be thought of as a race, with only the fastest toads at the frontline. These athletic toads inevitably breed with each other, because all the slow toads have been left behind. Some of their offspring inherit 'speedy' genes from both parents and thus the rate of invasion increases every year."

The process of "spatial sorting" relies on genes for speed accumulating at the increasingly fast-moving frontline. Unlike natural selection - a process first described by Charles Darwin, stating that traits which help an organism survive and reproduce will build up over time - spatial sorting does not require an animal's survival or reproduction to be increased by it being quicker. The new process can only work within the limits set by natural selection, but may be an important cause of evolutionary change in species that are expanding their ranges into new territory.

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Skeptic_Heretic
4.4 / 5 (5) Mar 23, 2011
Professor Shine said the process, which depends on "mating between the quickest" rather than "survival of the fittest", challenges the long-held view that natural selection is the only driving force for evolution.

The author, or perhaps the scientist needs to re-read Darwin. It was never survival of the fittest, outside of a set of misprinted German language versions of the original text.
kaasinees
1 / 5 (1) Mar 23, 2011
Ya just look at Koalas. They are hella fit.
jamesrm
5 / 5 (3) Mar 23, 2011
en.wikipedia.org/wiki/Survival_of_the_fittest

Darwin first used Spencer's new phrase "survival of the fittest" as a synonym for natural selection in the fifth edition of On the Origin of Species, published in 1869.[2][3] Darwin meant it as a metaphor for "better adapted for immediate, local environment", not the common inference of "in the best physical shape".[4] Hence, it is not a scientific description.[5]

rgds
james
gunslingor1
3.8 / 5 (4) Mar 23, 2011
Agreed, what a rediculous mileading story, god this site is getting bad. I thought there was a breakthrough, instead, we get word play.

"mating between the quickest" rather than "survival of the fittest", challenges the long-held view that natural selection is the only driving force for evolution.

-WTF?! natural selection does not imply an improvement, it implies a mutation and in situ advantage.

This new process of evolution does not depend on survival or reproduction.

-WTF? really? so if all the toads were impotent, they would still get faster at the edges? rediculous.
-Really? there is no selective advantage to be on the edge of a swarm of invasive species? You can't think of anything? Perhaps you should study locus migration and mating patterns.

This is, by far, the worst story I've read on this site. It's like Fox news here.
Sin_Amos
1 / 5 (1) Mar 23, 2011
? WTF is right.
Ethelred
4.3 / 5 (6) Mar 24, 2011
Professor Shine said the process, which depends on "mating between the quickest" rather than "survival of the fittest", challenges the long-held view that natural selection is the only driving force for evolution.
Mating between the quickest IS natural selection. If being quick is needed to reproduce that is what it takes to FIT the environment. The environment includes the opposite sex.

"For over 150 years, biologists have believed that evolutionary change is caused by only two factors: survival and reproduction," says Shine.
Which is what he is showing here. Survival and reproduction. Has he been out in the noon day Sun too long?

"This new process of evolution does not depend on survival or reproduction.
Utterly false and it contradicts his own statement. IDIOT is what he is.

More
Ethelred
4 / 5 (4) Mar 24, 2011
"Repeated breeding between these fast-dispersing animals causes genes for rapid dispersal to become more and more concentrated in that zone."
Now that has meaning but it clearly does not show anything other than Natural Selection and he forgets the Founder Effect which is involved here.

The new process can only work within the limits set by natural selection, but may be an important cause of evolutionary change in species that are expanding their ranges into new territory.
True statement.

The study looks interesting but the bullshit is just that. It in no way shows a lack of natural selection. It EXPANDS on the idea of Natural Selection and EXTENDS the Founder Effect to continental sized islands.

Somebody, Dr. Shine cough, thought that Sound Bites were more important than actual science. Good study but idiotic remarks that were clearly false and contradicted the study. Thus his own personality has polluted his otherwise good work.

Ethelred
orsr
4 / 5 (1) Mar 24, 2011
Though I mostly agree with the critical comments above, nontheless I like to read something about the australian cane toad. The lack of natural predators makes it a perfect visible example of evolution in progress.
Also, I think what Dr. Shine tries to tell is, that natural selection is caused by the pressure which an organism is exposed to by its environment, whereas the proposed mechanism of "spatial sortion" is caused by the changes of distribution of an organism in space. Whether it is or isn´t part of natural selection is simply an issue of terminology.
gunslingor1
3 / 5 (4) Mar 24, 2011
I disagree, i think the guy is full of $hit. I mean, how the hell do you measure the speed of a toad? It's a intermittent jumping species that wanders forward without any significant goal of direction. Are you saying they jump faster or further, or are you talking about average distance traveled in a day? WTF?

Besides, common sense tells us the fastest of any species will obviously take the lead in any migration. Being at the head of the pack of an invassive species gives the leaders access to the untrambled un-used-up land ahead of a destructive swarm. So how is this not natural selection? The fastest eat all the good stuff before the slow can even get there, thus the slow die and the faster moves on to the next patch. Sure spatial distribution plays a role, so does temporal distribution, but no one is claiming time is a primary driver of evolution because it gives 0 insight into the universal process. This guy doesn't understand it at all, he really thinks he found something new.
Ethelred
5 / 5 (2) Mar 24, 2011
I like to read something about the australian cane toad.
Perhaps you might like to watch something as well.

http://www.youtub...XbRU9FP8

Poor Baz. Course a lot them buggers go those ways and worse. I am sure a few have been red and green in a blender as well.

whereas the proposed mechanism of "spatial sortion" is caused by the changes of distribution of an organism in space
A perfectly reasonable comment.

Whether it is or isn't part of natural selection is simply an issue of terminology.
That is a bit like saying the difference between Darwin and Lamark is a just a bunch of words. He blew it.

Ethelred
Youngster
1 / 5 (4) Mar 26, 2011
So, a toad that evolves into a toad is evidence of evolution?
kaasinees
3.4 / 5 (5) Mar 26, 2011
So, a toad that evolves into a toad is evidence of evolution?


So pikachu evolving into raichu is evidence of evolution?
Caliban
5 / 5 (4) Mar 26, 2011
So, a toad that evolves into a toad is evidence of evolution?


No, but a faster toad evolving from its progenitor toad population is, though.

Try to keep up, toad.

mm23
1 / 5 (4) Mar 26, 2011
Sent too soon.

It proves only natural selection, or micoevolution. Gene mutation. But it does not have one iota of proof of molecules-to-man. One can be true without the other being true.
210
1 / 5 (7) Mar 26, 2011
I have written it before and again now; the strict and hotly debated Darwinistic definition of evolution is TOO NARROW!
As we hypothesize and then see variations on the old-fashioned and strictly enforced idea of old school evolution, Mother Nature keeps displaying vestiges of 'other things' that appear, APPEAR to hold as valid a hold on the evolutionary throne as anything STRICTLY based on Darwinism...!
The ability to ADAPT has greater meaning than simple spurious mutation. Mutation alone cannot and does not explain or limit that force or blueprint that is guiding adaptive evolution.
-word-to-ya-muthas-
Bigblumpkin36
not rated yet Mar 27, 2011
I cant believe there are still idiots that dont believe in evolution, that just goes to show you dumb the world is cause of the bible. Ya god made a monkey retarded fish frog otherwise known as humans
jmcanoy1860
not rated yet Mar 28, 2011
Great. They've discovered the "founder effect".
breadhead
1 / 5 (3) Apr 09, 2011
Should have said, "I can't believe that there are still idiotic people around, who don't believe in creation. This just indicates how misinformed people in the world are, due to the teachings of evolution in public schools." If only people were not taught that living organisms evolved from in-organic elements. Please explain to me how DNA evolved.
Ethelred
5 / 5 (3) Apr 11, 2011
Should have said, "I can't believe that there are still idiotic people around, who don't believe in creation
There is NO evidence to support the Universe described in Genesis.

This just indicates how misinformed people in the world are, due to the teachings of evolution in public schools."
There is very little education in public schools about evolution until college. Ignorance of biology is the reason so many think there is no evolution.

All the fossils and lab tests and DNA sequencing show that evolution occurs. NOTHING shows that it doesn't. We do not need to know absolutely every step of evolution to know that it has occurred for billions of years. Hominid fossils alone are adequate evidence since there is no evidence against evolution. Just mindless remarks by the aggressively ignorant.

Please explain to my why not knowing how DNA evolved proves the world is less than 10,000 years old and the fossils are figments of the imagination.

Ethelred
J-n
5 / 5 (2) Apr 11, 2011
The ability to prove or disprove an idea is KEY to science and all knowledge.

The way that religions have created their gods and creation stories preclude any ability to prove or disprove, therefore cannot be thought of as science or as fact. EVER.

Infact why would a perfect being (god) plant fossils that to all accounts of science are many hundreds of times older than the earth? Is god trying to Trick humans? To Test them? Why use dinosaurs as a test when god already KNOWS how you would respond to them?

You see an omnipotent, omnipresent, omniscient god would NEVER need to test people as it would already know the responses, and would never need to trick someone as they could make what they want into fact.

Your god and beliefs do not pass the logic test. God gave you a brain? use it!