la brea tar pits/ humphreys

Hi Quetzal,Did you hear anything from Dr Offord, yet?I was browsing a bit and encountered your comments on the La Brea pit:Q: 2. The article states that an unexplainable "anomaly" is the ratio of carnivores to herbivores (more of the former than the latter).PB: Indeed, the La Brea fossils demonstrate a 10 to 1 ratio for herbivores and carnivores, of which 3 out of 10 are smilodon fatalis (sabre tooths).Q: 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.PB: I always thought that comparison of apples and oranges is allowed in evolutionism. Evolutionists do it all the time. They compare chimp to human to fishes to trees to whatever. So, this can hardly be an argument.Q: 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?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.Q: Herbivores are likely to avoid a carcass, not approach it, especially if there are carnivores around.PB: Probably the presence of carnivores alone would be sufficient.Best wishes,
Peter

Dear John,J: Your scenario of chain feeding carnivores would require an enormous population density of carnivores, an unreasonable density. What you propose would quickly wipe out the carnivores locally,PB: Actually these carnivores are wiped out: extinct.J: and by the time more colonize the area the trapped animals would sink into the muck and stop the cycle. Until another herbivore wandered into the trap.PB: Still the ratio is 10 carnivores to 1 herbivore. It puzzled me for a while. From ecology we know that emtied niches are pretty quick replenished by wanderers.. Probably the solution it is somewhere in between.BW, PB

Dear John,quote:
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Originally posted by peter borger:
PB: Actually these carnivores are wiped out: extinct.
--------------------------------------------------------------------------------J: LOL.... Yes, they are extinct, but that has nothing whatever to do with the scenario in question. You've missed the point.PB: Yeah, LOL isn't it?quote:
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PB: Still the ratio is 10 carnivores to 1 herbivore. It puzzled me for a while. From ecology we know that emtied niches are pretty quick replenished by wanderers.. Probably the solution it is somewhere in between.
--------------------------------------------------------------------------------J: But your chain feeding scenario would wipe out local populations of carnivores before the more distant populations colonized the area. Not to mention that it would drive the carnivore/herbivore ratio way up from 10-1 to 100-1 or more.PB: I am interested in your calculations.Best wishes,
Peter

quote:
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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.
--------------------------------------------------------------------------------Q: 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.PB: I read somewhere that it would take 30-50 ky to fill up the tar pit. I am glad that we agree that couple of centuries would also suffice.Q: 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!PB: I only attack evolutionism where I have a sure case.Best wishes,
Peter