Lamarkian Evolution.

I wonder how many people have actually heard about this. I know what it is, but do any of you?

And also am I going to be the only one to make topics in this?

i dont know about it. tell please, is it something with flying meatman? lol

i heard of it in a book. i think its thwe wrong theory.

lamark: garafes had long necks because they wanted to get long necks so they could eat leaves when they tried to make ther neck longer it went longer magic.


darwin: the ones that could reach the leavves have babies and the ones that dont eat the leaves die so the garafes all become long neckiid

think i heard this oor maybe its all wrong

Simplified, but yes. However it's not QUITE that. Lamarkian actually says that the experiences of the individual are transferred over to the offspring. Like genetic memory, only SUPER genetic memory. Some of you may recognise this from some sci-fi things. Anyway, yeah, your definition is pretty much it. Obviously it didn't really hold up. At least with nothing on this planet.

yea I heard in 7th grade biology. but very little about it.

While Lamarckism has been discredited as an evolutionary influence for larger lifeforms, some scientists controversially argue that it can be observed among microorganisms.[15] Whether such mutations are directed or not also remains a point of contention.

In 1988, John Cairns at the Radcliffe Infirmary in Oxford, England, and a group of other scientists renewed the Lamarckian controversy (which by then had been a dead debate for many years).[16] The group took a mutated strain of E. coli that was unable to consume the sugar lactose and placed it in an environment where lactose was the only food source. They observed over time that mutations occurred within the colony at a rate that suggested the bacteria were overcoming their handicap by altering their own genes. Cairns, among others, dubbed the process adaptive mutation.

If bacteria that had overcome their own inability to consume lactose passed on this "learned" trait to future generations, it could be argued as a form of Lamarckism; though Cairns later chose to distance himself from such a position.[17] More typically, it might be viewed as a form of ontogenic evolution.

There has been some research into Lamarckism and prions. A group of researchers, for example, discovered that in yeast cells containing a specific prion protein Sup35, the yeast were able to gain new genetic material, some of which gave them new abilities such as resistance to a particular herbicide. When the researchers mated the yeast cells with cells not containing the prion, the trait reappeared in some of the resulting offspring, indicating that some information indeed was passed down, though whether or not the information is genetic is debatable: trace prion amounts in the cells may be passed to their offspring, giving the appearance of a new genetic trait where there is none.[18]

Finally, there is growing evidence that cells can activate low-fidelity DNA polymerases in times of stress to induce mutations. While this does not directly confer advantage to the organism on the organismal level, it makes sense at the gene-evolution level. While the acquisition of new genetic traits is random, and selection remains Darwinian, the active process of identifying the necessity to mutate is considered to be Lamarckian.

You might was to remove the reference numbers when you copy from wiki.

Incidentally, I understand Lamarkian as my explanation. What that says simply sounds like adaptation, which is mutation chosen for by natural selection. While it makes sence that bacteria can "activate" their mutations, what one's survive and what don't, as is admited there, is a process of natural selection. What Lamarkian is is the organism's EXPERIENCES being passed on. Whethere this is on purpose, like my kid will know what I know, or at a gentic level is one of the questions about it. And obviously in higher organisms it's certainaly not purposeful. However, an activation of a bacteria's DNA and mutation therein, if that mutation is chosen to suceed, it would obviously be passed on. This is Darwinian evolution, not Lamarkian. So I don't know who wrote that definition. Unless I'm misunderstnding it.

Plus I doubt that the bacteria, them BEING bacteria, would see a "need" or have a "desire" to mutate. Bacteria simply mutate EXPONENTIALLY, thusly allowing obvservation of the natural selection process over a very "long" period. Subsequentaly, said bacteria would mutate so that they may survive the herbicide. If they're lucky enough to HAVE this mutation at the time, of course.