la brea tar pits/ humphreys

Hi graedek,I'm not sure what you're looking for inre Rancho La Brea. I'm not familiar with the creationist claims here - maybe you can fill me in? The Page Museum is the main website for the Los Angeles Museum of Natural History on La Brea, so maybe you'll find what you're looking for there.

Hi forgiven. Missed this reply the first time around. I guess thanks are owed to Brad for resurrecting this thread from the depths.

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quetzal, i think the creationist view runs something like, there's at least one area (i've read many), only about 4 cubic feet, in which so many fossils are located, from so many different types of creature, that it would be impossible without the 'catastrophic' scenerio (ie the flood)... you might wanna look into that, i haven't been able to find any website that even attempts to explain the occurance in evolutionary terms

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I've honestly never heard this claim before. Could you post a link to one of the creationist sites that describes the issue? The problem is that the journals I normally frequent don't appear to have addressed the issue at all (or at least not in those terms). To me, this indicates it might be a non-issue from a scientific standpoint. OTOH, I may just be looking in the wrong place or using the wrong search terms. Thanks.

Hi Graedek,Thanks for the link. I was wondering what the actual claim was.There seem to be several areas that the article you linked claim are "impossible to explain from an evolutionary standpoint" (I always wonder where creationists come up with this idea). I'm not going to try and rebut every single argument in the article (you can explore the Page Museum website I linked to if you're actually interested), but I would like to bring out a few of the specifics for consideration.1. The article appears to state there are "too many fossils" to be explained by entrapment events. The actual case is that, while there have been millions of specimens recovered, the actual number of individual animals recovered is consistent with about ten large mammals being trapped every decade over a period of 30,000 years. Not an overwhelmingly impressive number. The article disingenuously neglects to bring out this distinction.2. The article states that an unexplainable "anomaly" is the ratio of carnivores to herbivores (more of the former than the latter). The article tries to draw a spurious comparison with the ratios in living populations in Africa and Canada, (ratios which are dependent on energy flow and carrying capacity in an ecosystem). In other words, they're trying to compare apples and oranges. The only way this comparison can even be remotely viable is if all entrapment of every animal was completely random and dependent on population density. That isn't the case. One herbivore (say a mammoth) gets trapped. A pack of dire wolves comes in to feed on the unlucky victim and several members are in turn trapped. How many herbivores were trapped and how many carnivores? Isn't it also possible that trapped carnivores might in turn attract even more carnivores or scavengers? Herbivores are likely to avoid a carcass, not approach it, especially if there are carnivores around.3. Too many eagles. Apparently the author of the article is unaware that eagles, as well as being good hunters, are also quite opportunistic scavengers. How many doves have you seen feeding on dead animals? The same idea as with mammalian carnivores applies. Something gets stuck, something else comes to eat it and also gets stuck. It's also fairly easy to dismiss the comparison to the Arizona tar pit left by a road crew that is the only counter-example the author tries to use to refute the "trapped herbivore attracting carnivore" explanation. Note one glaring discrepancy in that refutation? See any large mammals being trapped in the Arizona example? See any reason for an eagle or other known scavenger bird to land in it?4. The article claims there are too many landbirds vs waterbirds. Excuse me? Tar looks like water? The tarpits are a land-based phenomenon. Why is it surprising that land based birds such as turkeys would be more likely to wander in...?5. Damaged bones. I'm going to quote the article directly, here.

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The superior grade of preservation that characterized the individual specimens stood in stark contrast to the ravaged appearance of the fossil material as a whole. A majority of the bones were damaged in some way: sharp-edged broken ends, splinters, cracks, impact depressions, deep grooves, broken-off chips, and/or heavy abrasions.

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And the explanation that the article seems unaware of: Conditions of fossilization from the Page Museum site.I think that's enough for now. I hope I've shown that yet another CRS article doesn't hold up very well under any kind of scrutiny.

Hi Peter:

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Did you hear anything from Dr Offord, yet?

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Nope, and given the amount of time that has lapsed, I doubt whether I will. She may be one of those people who simply don't answer email questions from non-colleagues. No matter - it merely means we will simply disagree on that one minor point until/unless one of us can come up with other data. Have you heard from Dr. Peakall?

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PB: ...and upon the entrapment of the carnivores more packs of carnivores came, who became entrapped, and that attracted more carnivores, who became entrapped, that attracted more canrivores, etcetera. So, it probably took only a couple of centuries to fill the tar pit with thousands of skeletons. It elegantly explains the 10:1 ratio.

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I'm not sure of the sequential carnivore part, but I agree that it wouldn't take much time to fill the various tar pits. As I pointed out, the number of individuals found equates to roughly to ten large mammals a decade. I also agree that the carnivore-herbivore ratio is explained by the "attraction" hypothesis.Were you agreeing with my post? I honestly had to read your response a couple of times to be sure, but it sounded like it. If so, this may be a first!