TagliatelliMonster
Veteran Member
You’re wrong, to some degree.
I'm not.
Not genetic manipulation
Then there's nothing artificial about the mutations.
, but Lenski and his associates, in several experiments, have reduced certain pressures, and increased others, to rates that aren’t normally found.
Pressures are just environmental conditions. If a volcano erupts, it drasticially changes selection pressures in the immediate environment as well.
This isn't any different from changing the temperature in a freezer.
In such experiments, researchers will typically alter the environment on a relatively frequent basis. And they'll do that in order to accelerate evolution. This is the principle of Punctuated Equilibrium. At some point, a species living in an unchanging environment will reach a "local optimum". Meaning that it will have reached some sort of "maximum adaption" level, from where there no longer are any easy evolutionary pathways towards more improvement / optimization.
At that point, natural selection will favour the status quo and evolutionary change will slow down heavily or even come to an as-good-as halt. Changing the environment, changes the selection pressures. Changing the selection pressures, moves the species out of its local optimum. At this point, the status quo is no longer favoured. Evolution accelerates again.
Again, this is not unlike what we see in nature. In nature, conditions rarely, if every, stay the same. There are periods of stability, sure, but they will never stay that way. Sooner or later, change will happen. Sometimes sudden "shock" changes (like when a volcano erupts", other times slow and gradual changes (like geological activity slowly making a river form with all the consequences it brings).
Return that E. coil strain to the wild...it couldn’t defend itself; it would lead to extinction. Why? Because it lost function.
No. Rather because it evolved to fit a different habitat. That habitat being, the enivronment of the experiment.
This is just like taking a salt water fish and putting it in sweet water. It won't survive either.
Not because it "lost function", but simply because it evolved to fit the salt environment, to the point where it can only survive there. A "shock" change like suddenly ending up sweet water, usually means certain death.
In the “Long Term”? Bacteria will stay bacteria.
And eukaryotes will stay eukaryotes.
And vertebrates will stay vertebrates.
And tetrapods will stay tetrapods.
And mammals will stay mammals.
And primates will stay primates.
And homo sapiens will stay homo sapiens.
And, you guessed it, homo sapiens still ARE: homo sapiens, primates, mammals, tetrapods, vertebrates and eukaryotes.
A new species, maybe. But that’s not disputed.
Sounds like what you are disputing, is nothing but a strawman.
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