Posted on 07/16/2010 6:19:00 PM PDT by swatbuznik
One of the evolutionary concepts that is frequently argued over is the concept of “speciation”. Imagine an animal somewhat like a lion. Through evolution, it might become an animal somewhat like a tiger. These would be considered different species and could not interbreed. (Of course, Ligers do exist, because lions and tigers actually can interbreed … but let’s not get messy right away, shall we?
Anyway, no one really knows how to define a species, and there is controversy about any proof that one species has ever become another species. The concept of Ring Species is sometimes mentioned as pretty good proof. But Ring Species seem to provide evidence of salamanders turning into … salamanders. And seagulls turning into … seagulls. Not everyone is impressed by this.
So, we don’t know what species is, and we don’t know if any species has ever turned into another species (though the Theory certainly demands this).
Now, what’s higher than a Species? Well, in ascending order you get Genus, Family, Order, Class. Now we’re at a pretty high level. An example of a Class would be “mammal” or “fish”. No one in their right mind imagines that a fish would – POOF! – turn into a mammal. That would be crazy, right?
What’s above Class? Well, at an even higher level you have a Plylum. An example would be Vertebrates or mollusks. A scallop turning into a mammal? I don’t think so. Hey, wanna know what’s really interesting about the Cambrian Explosion?? That’s when almost all the Phyla suddenly appeared. Basically, 600 million years ago, Phyla just started popping into existence. It’s not clear that there was much of anything as an intermediate step. One day you have mollusks, then the next day you have vertebrates. Wild, huh? I don’t think a nifty invention like sperm will help a mollusk suddenly evolve into a whole new Phyla – like a vertebrate -- but who knows?
Now, remember, we have a hard time really explaining lions and a tigers and speciation and how they might have evolved within the Felis genus. No really good explanation for that – just a Theory. We call them species but we don’t really know what we mean when we say that. But, 600 Million Years Ago (so they say) much more magic things were happening – POOF!
LOL... Nicely done.
“and is found in almost all animals”
It gets there in many ways....
im with you
I’m glad that you responded to this thread. Your post was fun to read.
Heh heh heh!
I agree with the basic premise of your reply about our poor definition of what a species actually is, affecting whatever we deduce about things involving them. I guess it’s the limitation of mankind trying to force static standards onto an ever-changing, happily dynamic system.
Another discussion on the same vein would be on arguing about when an individual human life actually begins, if it has a “beginning” at all, in the first place. At conception? But the gametes that were involved were also ‘alive’ based on how we choose to define what ‘life’ is!
LOL!
A human egg is alive. It, by itself, is not a human since it has only 23 chromosomes. Humans have 46.
A human sperm cell is alive. It, by itself, is not a human since it has only 23 chromosomes. Humans have 46.
Put them together at conception and you have a living cell with 46 chromosomes which define a unique human individual. Voila!
Nice, but it again rests on the assumption that human life requires 46 chromosomes to be “alive”, right? The two gametes are not “lifeless” in the sense inanimate objects are lifeless, before their fusion.
A human egg is alive. It, by itself, is not a human since it has only 23 chromosomes. Humans have 46.
A human sperm cell is alive. It, by itself, is not a human since it has only 23 chromosomes. Humans have 46.
Put them together at conception and you have a living cell with 46 chromosomes which define a unique human individual. Voila!
They're just haploid forms of humans... they are still human and still alive. They just don't have the intellect or complexity of diploid humans.
In genetics class, we discussed the fact that every species alternates between haploid and diploid generations. In humans, the haploid generation is quite short. In some other organisms (mostly fungi and plants), individuals live their whole lives as haploids... the haploid form is as significant as the diploid, or, in some cases, is the dominant form of the species and the diploid is only transitory.
Nature really gives us some fascinating permutations of life.
It’s worth remembering that the Cambrian “Explosion” actually took between 10 and 80 million years. In other words, 5 to 20 times as long as anything like humans have been around. Not so much of a “poof,” really.
Exactly. That was the gist of my reply before yours, too.
True.
The “explosion” is only relative to the latter stages of relative “stability”.
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Thanks swatbuznik. |
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Thank goodness Helen Thomas was already post menopausal when this happened.
MSNBC promotes evolution and allows their people to mock creationists - stupid station
Oh, that’s funny. :-)
Because
Every sperm is sacred.
Every sperm is great.
If a sperm is wasted,
God gets quite irate.
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