"But They're Still..."
I'm about sick of pointing creationists towards lists of observed instances of evolution in action where said creationist immediately turns around and spouts off with a well-rehearsed "but they're still (insert "kind" here)!!!"
A recent example that jumps right to the front of my mind is when a certain creationist was confronted with the existence of nylon-eating bacteria. His response?
Yeah, you guessed it.
The following will be a little biology lesson for all of you "they're still bacteria" people.
The old system of taxonomy, in which Kingdoms were the broadest order of life, is in the process of being revised in favor of a Three Domain System. Those three domains are Archaea, Eubacteria and Eukaryota. For those who lost their geek-speak translators, Archaea includes Archaebacteria, Eubacteria covers all of the other types of bacteria and Eukaryota covers everything that doesn't fit into either of the previous two. Yes, dear: you and I are in the same domain as trees, flowers, bugs and, God forbid, apes. This, of course, makes perfect sense since our cells have more in common with trees than with prokaryotes (read: membrane-bound compartments).
Archae are set apart from regular bacteria because of their lack (in all but one group) of a peptidoglycan cell wall. While, like other cells, they have a cell membrane composed of a phospholipid bilayer, the actual chemical makeup of the membrane is different in the Archaea domain than in regular bacteria and eukaryotes. While I find archaebacteria to be pretty much cool as hell because species in this domain can be found in the the most hostile of conditions, our focus here is going to be on regular bacteria, since we're talking about a creationist canard and not about some class lecture.
To answer the creationist canard, I offer the following: to date there are over 7000 indentified species of bacteria split between just over twenty subgroups inhabiting our little chunk of rock. Plenty of room for diversity here. Bacteria are the most abundant forms of life on the planet (they must have received the "Go ye forth, be fruitful and multipy" commandment first).
Next time you, the creationist, insists that "they are still bacteria", remember that if you take two random species from two random subgroups for further study, you might find that they have less in common genetically than your own DNA has with that of a barrel cactus. Would you like it if I referred to you and your family dog in the same dismissive way ("but they're still eukaryotes!")? Your argument for "kind" fixity is no more valid than if you were to actually accept that humans and apes share a common ancestor yet still deny evolution because "they're still multicellular". That last one sound ridiculous? Maybe that's because it is... but my comparison stands, whether you like it or not.
Ditch the argument... and please: have some respect for our microbial conquerors.
8 Package(s) of Returned Poo:
Hey, great site, I just read nonstop through the Hovind Files (you poor bastard, trying to watch that junk).
I was on the receiving end of this canard recently. The actual usage was "A finch may change its beak size but it'll never turn into an eagle". Was forced to point out, in words of one syllable, that finches and eagles aren't in the same genus. They're not even in the same family. They're not even in the same order.
Thus, we wouldn't actually expect to see a finch change into an eagle, any more than we'd expect to see an oak tree do a jack-and-the-beanstalk impression and appear overnight. What we would expect to see is slight growth of twigs with the occasional bifurcation thereof. The tree-of-life equivalent of that is precisely what we do in fact see.
What is there that's so hard about this concept that so many people get stuck on it? Daft question, I guess - cover yourself with superglue and there's no limit to what you can get stuck on if you so wish.
I was discussing this with a good friend of mine who has a MSc in evobio. We were talking about the whole "you can breed poodles and get a St. Bernard, but you'll never get a cat" and my friend pointed about that, while it would probably take longer, you could certainly breed something from poodles that looked and acted very much like a cat from the outside. Genetically and biochemically it wouldn't be a cat, but then a dog that had all the exterior characteristics of a St. Bernard, but was bred from poodles would probably be genetically as different from a St. Bernard as the original poodles are. Basically, the argument is pointless and useless and stupid and stoooooopid and dumb and...
Sorry. I get carried away with morons.
my friend pointed about that, while it would probably take longer, you could certainly breed something from poodles that looked and acted very much like a cat from the outside.
Similarly, by putting marsupials under appropriate natural selective pressures, you can produce something that's pretty dog-like.
But, of course, God obviously just chose to create two distinct species that were completely different structurally but that just happened to resemble each other a lot... *groan*
Can I just add (reiterate) that all the taxonomy categories were made up by PEOPLE and do not have some meta-meaning except as a system of classification that is based on like 300 years of observations?
Thanks.
They also don't seem to get that descent and ancestry are irrelevant to extinction. In other words, a particular species can produce a distinct new species without the original having to go extinct, and the original can continue to evolve separately.
and the crazy concept that individual does not equal group.
"and the crazy concept that individual does not equal group."
I never really looked at it this way, but creationists using this argument are actually stereotyping bacteria just because of what they are. Now I'm going to have to go start a bacterial rights advocacy group... maybe I can call it the NAAPO (National Association for the Advancement of Prokaryotic Organisms).
Ahh, forget it. They advance themselves just fine without our help, and will continue to do so long after we are extinct.
Hey, you've solved the mystery of how Noah got a few of each Kind (TM) on the Ark. A few each of Archae and Eubacteria, himself and a few family members covering the Eukaryotes, and that's it. The rest of the Ark was, I dunno, maybe a casino or something. Who knew that Noah was so up on modern biology>
did
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