A Toxic Cane Toad: Super-quick evolution has allowed the cane toad, above, to invade Australia at a rate of 30 miles per year today, compared with seven miles per year in the 1950s.
Posted on 02/15/2006 1:30:20 PM PST by PatrickHenry
Fat, toxic toads at the leading edge of an Australian invasion have evolved longer legs than those behind the front lines, report biologists.
The alarming discovery not only means the toads can spread more quickly over the continent, but it raises the possibility that under the right conditions, animal evolution can happen in just decades, not eons.
That, in turn, has major implications for animals adapting to global warming, as well as biological pest control projects, which generally take for granted that carefully studied animals introduced to fight off invasive species can not evolve into something troublesome.
The inexorable, seven-decade-long expansion of cane toads from their disastrous introduction to Queensland in 1935 has long been monitored by biologists.
One such biologist was recently driving along a toad-crowded road one night, along the invasion front about 40 miles east of Darwin, when he noticed how desperately the toads were hopping grimly toward him, all facing the same way: into virgin territory.
"It was just like an invasion in a science fiction movie," said biologist Richard Shine of the University of Sydney.
Shine is a snake specialist, but when the toads began heading toward his study area, he decided it would be wise to "know thine enemy" before they arrived, he explained.
So for years Shine and his colleagues have been tracking cane toads, and as a matter of course they weigh the toads and measure them. Those records came in handy when they discovered that some cane toads at the invasion front were covering an unprecedented mile-and-a-quarter (two kilometers) each night.
"Sure enough, there was a pattern," said Shine of their astonishing leg-length discovery.
Not only were the legs of pioneer toads significantly longer, but the same athletic build dies out among toads as areas become more settled.
In other words, there appears to be a great advantage to getting the first crack at virgin territory. That boils down to the opportunity to produce more viable tadpoles that grow up to continue the line. For seven decades now that advantage has been awarded to cane toads with the longest legs. That has lead to the steady breeding of longer and longer-legged toads that can keep beating the crowd.
The disheartening result is that the toad invasion rate has increased from seven miles per year in the 1950s to a whopping 30 miles per year today, report Shine and his colleagues in the Feb. 16 edition of Nature.
The silver lining is that the cane toads are showing how quickly some species can adapt to new environments, a challenge now facing innumerable species worldwide as the global climate warms, said ecologist and rapid evolution researcher David Skelly of Yale University.
"We never think of evolutionary changes happening that fast," said Skelly of his fellow ecologists.
That has to change, because the cane toads are just a high profile case of something that is being seen in many organisms all over the planet, he said.
"It doesn't mean that we have no problem (with climate change) or that all species will be viable," said Skelly. But there is evidence that many species might be more able to adapt than previously believed.
Another place where people have to start thinking about rapid evolution is at the federal and state agencies where they evaluate exotic species for release as biological checks on exotic pests, said Skelly.
Right now those agencies don't consider the possibility that a new exotic species will very likely change in its new environment, for better or worse. It's time they started thinking differently, he said.
Whether we are a major factor in climate change or not we need to evaluate the affects on other species and determine what costs to them and to us we are willing to accept.
Personally I feel we've reached a limit and need to rethink our methods but see no consensus to do so.
If other species are so successful at evolving so quickly to adapt to global warming, we (homo sapiens) are going to be soon left out in the cold, so to speak.
Well there's the beginnings of a science fiction movie! ;)Of course, we do still own the ability to start a fire and shoot a gun, so I guess we win after all! LOL!!
This is understandable, at soem point the pioneer toads outgrew the beds in the pioneer toad motels causing back problems from sleeping on the floor. At which point the tortoise toads won the race.
Not so! Just a couple of days ago there was a thread warning of another little ice age on the horizon. Could that scientist have been wrong?
The problem is that most quick adaptation is through the selection of an existing allele(s). If the species has no allele that confers necessary adaptations it is less likely to survive. The survivability of a species is heavily dependent on the speed of the environmental changes; the changes we see occurring in present ecosystems are too fast and furious for many species to survive.
Diversity will drop dramatically before vacant niches encourage a rebound diversity increase. What will that cost us? - How will that affect our survivability. - What are the ethical costs?
Please provide some evidence for this claim.
What's your conjecture of what is on the horizon? Is it global warming or another ice age? I didn't see the thread.
Common usage will prevail.
Not in science. These definitions are much closer to what scientists use:
Definitions (from a google search, with additions from this thread):
Theory: a well-substantiated explanation of some aspect of the natural world; an organized system of accepted knowledge that applies in a variety of circumstances to explain a specific set of phenomena; "theories can incorporate facts and laws and tested hypotheses." Addendum: "Theories do not grow up to be laws. Theories explain laws." (Courtesy of VadeRetro.)
When a scientific theory has a long history of being supported by verifiable evidence, it is appropriate to speak about "acceptance" of (not "belief" in) the theory; or we can say that we have "confidence" (not "faith") in the theory. It is the dependence on verifiable data and the capability of testing that distinguish scientific theories from matters of faith.
Hypothesis: a tentative theory about the natural world; a concept that is not yet verified but that if true would explain certain facts or phenomena; "a scientific hypothesis that survives experimental testing becomes a scientific theory"; "he proposed a fresh theory of alkalis that later was accepted in chemical practices."
Proof: Except for math and geometry, there is little that is actually proved. Even well-established scientific theories can't be conclusively proved, because--at least in principle--a counter-example might be discovered. Scientific theories are always accepted provisionally, and are regarded as reliable only because they are supported (not proved) by the verifiable facts they purport to explain and by the predictions which they successfully make. All scientific theories are subject to revision (or even rejection) if new data are discovered which necessitates this.
Law: a generalization that describes recurring facts or events in nature; "the laws of thermodynamics."
Model: a simplified representation designed to illuminate complex processes; a hypothetical description of a complex entity or process; a physical or mathematical representation of a process that can be used to predict some aspect of the process.
Speculation: a hypothesis that has been formed by speculating or conjecturing (usually with little hard evidence). When a scientist speculates he is drawing on experience, patterns and somewhat unrelated things that are known or appear to be likely. This becomes a very informed guess.
Guess: an opinion or estimate based on incomplete evidence, or on little or no information.
Assumption: premise: a statement that is assumed to be true and from which a conclusion can be drawn; "on the assumption that he has been injured we can infer that he will not to play"
Impression: a vague or subjective idea in which some confidence is placed; "his impression of her was favorable"; "what are your feelings about the crisis?"; "it strengthened my belief in his sincerity"; "I had a feeling that she was lying."
Opinion: a personal belief or judgment that is not founded on proof or certainty.
Observation: any information collected with the senses.
Data: factual information, especially information organized for analysis or used to reason or make decisions.
Fact: when an observation is confirmed repeatedly and by many independent and competent observers, it can become a fact.
Religion: Theistic: 1. the belief in a superhuman controlling power, esp. in a personal God or gods entitled to obedience and worship. 2. the expression of this in worship. 3. a particular system of faith and worship.
Religion: Non-Theistic: The word religion has many definitions, all of which can embrace sacred lore and wisdom and knowledge of God or gods, souls and spirits. Religion deals with the spirit in relation to itself, the universe and other life. Essentially, religion is belief in spiritual beings. As it relates to the world, religion is a system of beliefs and practices by means of which a group of people struggles with the ultimate problems of human life.
Belief: any cognitive content (perception) held as true; religious faith.
Faith: the belief in something for which there is no material evidence or empirical proof; acceptance of ideals, beliefs, etc., which are not necessarily demonstrable through experimentation or observation. A strong belief in a supernatural power or powers that control human destiny.
Dogma: a religious doctrine that is proclaimed as true without proof.
[By the way, based on these definitions evolution is a theory. CS and ID are beliefs.]
[Last revised 2/9/06]
Interesting....on all counts. Especially in terms of costs. Since we cannot, to any significant degree, control global warming or cooling, can we adapt quickly enough to survive over other species who have already physically adapted?
Sorry, not for breakfast. We archaeologists take our work very seriously.
But on occasion, with the after-dinner coffee in a wilderness camp on a very cold night, a little cognac can be a fine thing!
The probability of that is 1. We are here.
Thanks for the ping.
Science has built-in mechanisms to flesh out and expose frauds.
Howzabout Religion? Name one rigorous mechanism that religion has to expose frauds.
I mean just look at the LDS -- started by a fraud and now one of the largest churches around. Scientology, ditto.
The Kettle in the Glass House.
The probability of that is 1. We are here.
Might be best to stick with predicting politics, baseball and golf. Did you know the Steelers were going to have their 12th man calling the plays? ;)
I like that. LOL! Is this what the most highly evolved of the toad species will resemble? At some point it might be man against hypnotoad.
This is how the acceptance of Darwin as actual science has dumbed down the masses: unfortunately, kids and adults read this garbage and actually believe it supports evolution. I bet if someone would challenge this in the courts, those brilliant justices would support the author and call it legitimate science.
Oh, and I guess if our kids are'nt taught this junk, they could never be "real scientists'
At first I thought this was from The Onion!
You're conflating hindsight and foresight. I'm very good at the former, average at the latter.
Is the 12th man the guy who gets called for a blocking low penalty while making the tackle? Wrong team, my mistake. :-}
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