The main reason I’m posting this is because my sister’s boyfriend is probably going to register here at some point, and since he’s a creationist I’d like to explain it to him. But I don’t think this has been explained recently to the newest group of creationist here either, so I think it’s worth pointing out to them also.
Most creationist organizations admit that evolution can cause small-scale changes, including the formation of new species. For example, AiG has the claim “new species never form” on their list of
arguments that creationists should not use. However, if you read the rest of what AiG says about this, you’ll see that they think speciation can only occur within the confines of certain “kinds” of organisms:
Originally Posted by Answers in Genesis “No new species have been produced.”
This is not true—new species have been observed to form. In fact, rapid speciation is an important part of the creation model. But this speciation is within the “kind,” and involves no new genetic information.
As far as I can tell, AiG doesn’t offer a very clear definition of what genetic “information” actually means in this case, but Caravelair posted an excellent explanation in
this thread of how by almost any definition of the word, information can be increased by mutations. It should be clear from Caravelair’s thread that AiG is wrong about mutations being unable to increase information, but what about their more general claim that evolution is restricted within certain “kinds”?
Before I can address this question, first I ought to know exactly what “kind” means in this case, and unfortunately AiG isn’t any more specific about this than they are about the definition of “information”. After searching Google and Wikipedia for a little while, the only thing I was able to find for certain about this is that creationists generally disagree about it.
This article describes a few different hypotheses about what constitutes a “kind”.
The most common definition of “kind” seems to be the same as “family” in the Linnaean system of taxonomy, so all canids are the same “kind” but are a separate kind from felines. For the sake of the argument, though, I’m going to apply an even broader definition to “kind” and assume that it exists on the order or class level in taxonomy. If I can provide an example of one class of animals evolving from another, that would be an example of evolution outside the confines of a “kind” by just about any definition.
Those of you who have been here for a while might remember what my favorite area of evolution is, so you can probably guess what example I’m going to use. Here are the two animals between which I’m going to try and show a relationship.
The first is unequivocally a dinosaur, which means it’s either a reptile or a sauropsid, depending on whose classification system you use:
Kingdom: Animalia
Phylum: Chordata
Class: Sauropsida (or Reptilia)
Superorder: Dinosauria
Order: Saurischia
Suborder: Theropoda
Infraorder: Coelurosauria
Family: Compsognathidae
Genus: Compsognathus
Species
Compsognathus longipes
The second is clearly a bird (AiG claims it has nothing uniquely dinosaurian about it; I’ll deal with that claim a little later.)
Kingdom: Animalia
Phylum: Chordata
Class: Aves
Order: Archaeopterygiformes
Family: Archaeopterygidae
Genus: Archaeopteryx
Species:
Archaeopteryx lithographica
Now, I’m assuming AiG wouldn’t have a problem with Compsognathus being related to another dinosaur within the same family Compsognathidae, since according to the most common definition of “kind”, members of the same Linnaean family are the same “kind”. This animal, Sinosauropteryx, is nearly identical to Compsognathus in terms of its skeletal anatomy. The one major difference is that the fossils of Sinosauropteryx preserve a cover of primitive feather-like integument:
Kingdom: Animalia
Phylum: Chordata
Class: Sauropsida
Superorder: Dinosauria
Order: Saurischia
Suborder: Theropoda
Infraorder: Coelurosauria
Family: Compsognathidae
Genus: Sinosauropteryx
Species:
Sinosauropteryx prima
Unless you assume this “dino-fuzz” is the same structure as the feathers found on modern birds (and most creationists don’t), there are only a dozen or so known species that have it. Even if AiG wouldn’t approve of considering animals to be the same “kind” based on a unique trait they share that’s not found in any other group, some of the other animals in this group are anatomically so similar to Sinosauropteryx that I don’t think it could be considered anything other than “micro evolution” for it to be related to them. Jinfengopteryx, for example:
Kingdom: Animalia
Phylum: Chordata
Class: Sauropsida
Superorder: Dinosauria
Order: Saurischia
Suborder: Theropoda
Infraorder: Coelurosauria
Family: Troodontidae
Genus: Jinfengopteryx
Species:
Jinfengopteryx elegans
The main differences between this animal and Sinosauropteryx are that the dino-fuzz on Jinfengopteryx bears a much stronger resemblance to actual feathers. The resolution if this image isn’t great, but it’s fairly easy to see that in its tail they consist of rows of barbs attached to a central shaft. The animal clearly isn’t a bird, though—its pubis points forward rather than back, and its forelimbs aren’t arranged in such as way that it could fold them or flap them the way some of the more bird-like dinosaurs could.
A slightly more bird-like dinosaur is
Sinornithosaurus. (I’m just posting a link to this one, because I think it deserves a higher resolution image than it’s possible to post directly.)
Kingdom: Animalia
Phylum: Chordata
Class: Sauropsida
Superorder: Dinosauria
Order: Saurischia
Suborder: Theropoda
Infraorder: Coelurosauria
Family: Dromaeosauridae
Genus: Sinornithosaurus
Species:
Sinornithosaurus millenii
This specimen of Sinornithosaurus is the fossil that convinced my sister that dinosaurs are related to birds. It has the same sort of contour feathers that are present in Jinfengopteryx, but in other respects its skeletal anatomy is more birdlike than that of any of the other dinosaurs I’ve mentioned so far. Although it probably couldn’t fly, the muscle attachment points of its forelimbs and wishbones show that it was capable of flapping its arms in almost the exact same manner as a bird, which it probably would have used in order to grab hold of whatever smaller animals it hunted for food. In other respects, however, it was clearly a dinosaur: its skull has very few differences from the skull of Velociraptor.
And finally, we have another dinosaur in the same family as Sinornithosaurus (and thus almost certainly the same “kind”): Microraptor.
Kingdom: Animalia
Phylum: Chordata
Class: Sauropsida
Superorder: Dinosauria
Order: Saurischia
Suborder: Theropoda
Infraorder: Coelurosauria
Family: Dromaeosauridae
Genus: Microraptor
Species:
Microraptor gui
I’ve already described this animal in a fair amount of detail
here, so rather than repeating everything I said there I’ll just say that it’s very similar to Sinornithosaurus. The main two differences are that it was much smaller, and that it was probably capable of a primitive form of flight. The long “wings” on its legs would have been more useful for gliding than anything else, and its primary feathers were asymmetrical, which is something used by modern birds to ensure that when they fly they push themselves up with each downstroke than they push themselves down with each upstroke. Microraptor is still considered a dinosaur and not a bird, though—it’s a member of dromaeosauridae, the group of dinosaurs that contains Velociraptor, and has the same retractable claw on the second toe of each foot that’s found in every member of this group.
This is the most bird-like dinosaur currently known, unless you include birds themselves, so it’s especially worth comparing it to Archaeopteryx, the most dinosaur-like bird. The wrist structures of Microraptor and Archaeopteryx are nearly identical—they both have the unique crescent-shaped bone that allows them to fold their arms in the same manner as a bird’s wing. Both have a large wishbone to which flight muscles could have attached, although instead of the keeled sternum that modern birds use for this, they have a pair of unfused sternal plates as is typical for theropod dinosaurs. And finally, the Thermopolis specimen of Archaeopteryx shows that each of its feet had the exact same sorts of retractable second-toe claws that are found in Microraptor.
A more complete list of Archaeopteryx’s reptilian (dinosaurian) features can be found here:
http://www.talkorigins.org/faqs/arch...ptile-features
If you compare the classification of Microraptor to that or Archaeopteryx, you’ll see that they’re placed in two separate classes, which is ironic considering they’re every bit as similar to one another as Compsognathus is to Sinosauropteryx. However, the rest of the examples I’ve given should explain the reason for this: if Microraptor were classified as a bird rather than a dinosaur, why not include any of the other animals I’ve mentioned, such as Sinornithosaurus, which is only slightly less birdlike? Where do you draw the line? The problem is that in reality there isn’t any line at all—although creationists claim that there’s some sort of impassible barrier between higher-order Linnaean divisions such as classes, the division between animals of different classes is often just as fuzzy as it is between species within what they consider “created kinds”.
Each of these animals is only slightly more birdlike than the previous one, and the anatomical differences between one and the next is no greater than the differences between members of the same “kind”. However, if you were to consider each of these animals to be the same kind as the next, these small differences would add up to a very large one: that Compsognathus is related to Archaeopteryx, which AiG obviously won’t accept. As a result, what they claim is that some of these similarities are the result of the same “micro-evolution” within a “kind” that can be seen occurring today, whereas in other cases the similarity must only be a coincidence.
Think for a minute about the implications of this. If this were really true, there would be instances where two animals really are related to one another, and have all the similarities between them that one would expect if this were the case. But in other instances, God would have created animals that were so similar to others that they two
could have been related, but God was only making it look that way. Is that really the God described in your Bible? I don’t recall the Bible ever talking about God having gone out of his way to make things appear a particular way when they actually aren’t, and deceiving us into believing something that isn’t true.
I would hope that most Christians wouldn’t call their God a liar like this, but the only alternative is that these similarities aren’t a coincidence, and each of these animals is related to the next. Each one of these differences is small enough to be accounted for by “micro evolution”, but when you add up a whole bunch of individual instances of micro evolution, macro evolution is the inevitable result.
Linear Mode
