Giant Leap for Rodentkind

Masillamys, a rodent fossil dating to 40-48 million years old

Frank Sherwin – in Big or Small–Rodents Have Always Been Rodents –  appears to be arguing for a single rodent baraminological ‘kind.’ He claims, utilising a number of out-of-date or irrelevant references, that there is no evolutionary transition to rodents, but forgets that what he really needs to do is demonstrate that there are numerous distinct groups within rodentia that do not share a common ancestry. Why? Because a rodent kind would be simply too big! You’ll see what I mean in a moment.

Everyone is familiar with porcupines, beavers, rats, squirrels, and, of course, mice—common representatives of the order Rodentia or the rodents. They are defined by zoologists as having a single pair of constantly growing upper and lower jaw incisors. Over 40 percent (about 1,700) of mammal species are rodents.

Creationists often try to argue that a single pair of animals on the ark would be sufficient to create the genetic diversity within their claimed ‘kind’ that we see today, plus any other disparate extinct forms pointed out to them. But 1700 species is pushing it a little, especially as other sources give even higher numbers (over 2000). It’s therefore a safe bet that the position of a single rodent kind is indefensible, but that raises the question of why this higher grouping even exists? The existence of hierarchical groupings all the way to the top is an important line of evidence in favour of evolution – these need not exist in the world of the creationists, so why do they? And why do we fit into them, if we’re so special? Surely it would not be too much to ask of the almighty Creator to make his favoured group of fleshbags a class all of their own. Sherwin should be railing against these higher classifications, rather than using identical arguments to the usual ‘single kind’ claim.

They suddenly appear in the fossil record—as rodents. There is no trace of any ancestry linking them to non-rodent ancestors. The fossils are reasonably common, but they show no expected evolutionary progression. Paleontologist Michael Benton states, “The phylogeny [evolutionary history] of rodents is controversial.” Edwin Colbert writes:

Dr. A. E. Wood, one of our leading students of fossil rodents, has said, “The current status of rodent phylogeny and classification is such that anyone can point out inconsistencies in anybody else’s classification.”

I have a feeling that these are quote mines – or at very least irrelevant and several years out of date – but they are in books that I don’t have so I cannot prove it. But by ‘phylogeny’ they look to be talking about the internal relatedness of rodent groups, and not their “evolutionary history.”

Of course, in order for Sherwin to claim that rodents appear with no antecedents he must dismiss any evidence to the contrary:

Some of the latest evolutionary candidates for rodent ancestors are the Eurymylidae, from the early Tertiary of Asia. Recently, evolutionists suggested that a creature called Heomys may be the possible ancestor of rodents, although it is too advanced and its appearance is too late to be an ancestor. Other eurymylids such as Matutinia, Rhombomylus, and Eurymylus are a side branch and not directly ancestral to rodents.

“[T]oo advanced and its appearance is too late” – but is it a rodent or not? The same goes for the ‘side branch.’ His only citation for all of this is to The Osteology of Rhombomylus (Mammalia, Glires): Implications for Phylogeny and Evolution of Glires, which some quick digging suggests isn’t the last word on basal rodentia phylogeny.

In the pre-Flood and, possibly, post-Flood world, rodents achieved massive proportions. In 2000, scientists discovered Phoberomys, an extinct rodent discovered in Venezuela. Nicknamed Mighty Mouse or Ratzilla, they estimate that it weighed in at over a half-ton (1,500 pounds or 700 Kg)! The largest rodent today is the capybara, weighing a modest 150 pounds. Regarding Phoberomys, Benton stated, “At the time of discovery, it was said that ‘if you saw it in the distance on a misty day, it would look much more like a buffalo than a rodent.’”

Only ‘possibly’ post flood? Both this and his next examples are quite recent in the fossil record, and to a creationist would definitely have to be post flood. What exactly Sherwin is getting at here is beyond me.

An even larger South American creature was the formidable (and extinct) Josephoartigasia monesi, the largest rodent known. It could possibly have weighed 2,200 pounds to well over a ton. Meanwhile, North America had its giant beaver (Castoroides), growing over eight feet long and weighing 220 pounds (100 Kg), on par with the modern black bear. Its incisors were just under six inches long.

Again, the Josephoartigasia is quite a recent fossil (4-2 ma), as is Castoroides.

My guess is that Sherwin is trying to back up his titular “big or small” claim. However, size is but one (easily adjustable) variable in the rodent world – there is plenty else that would matter more. And we also have at the heart of this the ‘still’ idea.

Rodents are ‘still’ mammals. Mammals are still synapsids. Synapsids are still tetrapods. At the other end, mice are indeed still rodents, while humans are still apes and birds are still dinosaurs. This does not prevent evolution, because these groups are defined by characters, and these characters tend to be gained rather than lost – a human has all of the characteristics of a mammal, but also has those of an ape and of a human.

Sherwin has another irrelevant quote:

Fossils of mouse-size, 100 percent rodents have also been discovered in South America. They were evolutionarily dated at “41 million years old,” causing evolutionist Daren Croft to say, “This really pushes back the date of the first South American rodents.”

That’s from this 2011 ScienceDaily article. Sherwin apparently doesn’t realise, or at least wont tell, that rodents were already believed to have evolved tens of millions of years previously outside of South America, and thus this discovery has nothing to do with the price of fish.

His trumpeting of the “100 percent” (which seems to be his invention anyway, as I don’t think anyone is measuring) makes me wonder what he’d do with, say, “90 percent” rodents, and how you’d even calculate that. One of these ‘side branches’ might do the trick.

He concludes:

Along with openly questioning the extreme dates, creationists maintain the obvious: Rodents have always been rodents—created on Day Six, just thousands of years ago.

But how many were there on the Ark? That’s what I want to know.


Brian Thomas’ article for this month, Do Habitats Create Creatures?, is all but identical to the previous time he used that headline and thus does not justify its own post.

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6 thoughts on “Giant Leap for Rodentkind

  1. “I have a feeling that these a quote mines”

    Almost certainly … and I know a bit about that.

    http://www.talkorigins.org/faqs/quotes/mine/contents.html

    Here are a couple of sources re the quote:

    http://www.cryst.bbk.ac.uk/PPS2/assignments/A1/hys_info.html

    http://biostor.org/reference/4468.text

    It is the classic method of creationists. Find someone who says ‘hey, we don’t where this or that fits in’ and suddenly it’s an admission that evolution is wrong.

    The only real question is whether it is deliberate dishonesty or an example of the well-known ability of humans to fool themselves.

    • Well, it does seem clear that they’re not talking about what Sherwin claims they are – I think that’s all you really need to call it a quote mine. I’ll be using your list in future to check these things, anyway.

      Currently I’m cautious to take the ‘dishonesty’ line. I think the “well-known ability of humans to fool themselves,” amplified by what I see as a degree of intellectual laziness in many of the ICR’s articles, can take you a long way. Hanlon’s razor and all that.

    • Currently I’m cautious to take the ‘dishonesty’ line.

      That’s why I always frame these things as as asking the question of whether they are “lying” or “incompetent”, rather than positively asserting either. The implication being, of course, that regardless of the answer they shouldn’t be taken seriously as critics of evolutionary theory.

  2. Have you seen this?

    It makes my heart warm. Part 2 is more relevant to this post, but I find part 1 funnier.

    The flood story is actually more ridiculous than the Genesis creation account, to me. I’m amazed that anyone can study it to the depths these guys have and still cling on to it.

    • No I hadn’t – that’s hilarious!

      I wonder, have you ever linked that to a creationist and had them return (having watched only the first part) saying “that’s nonsense – Noah only needed kinds!” Because I wouldn’t be surprised.

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