New Clip from “Bringing the Sabertooths back to Life” film!

Now that all the filming for “Bringing the Sabertooths back to Life” is finished, we are busy with postproduction and editing. The film will be ready in a few weeks, but in the meantime I have uploaded a short clip for you to have a glimpse of a part of the complex process of reconstruction.

Participants in our Botswana art safari will be the very first people to see the finished film, which then is expected to premiere at Los Angeles in early Novemeber. I will keep you posted on any new developments.

And here is the link to watch the clip:

https://www.youtube.com/watch?v=CCbF6RR-fGs

 

Enjoy!

Posted on 07/08/2013, in Uncategorized. Bookmark the permalink. 5 Comments.

  1. So in your professional opinion, was North America a “predator limited” ecosystem? I read in a paper that proposed a trophic cascade model for the Quaternary Extinction in the Americas that at least North America had such a diversity of predators that competed directly with one another that the amount of prey animals was well below the carrying capacity of the environments on the continent. However, the paper also said that Homotherium was specialized to hunt mammoths which, is something you’ve already addressed on this blog.

    If it was, then does a trophic cascade model best fit the extinctions, or something else, like second-order predation?

    • That is a very interesting topic, but rather outside my expertise. Anyway, if you look at the African savannah today you see a guild of large herbivores that are controlled by an impressive array of large predators including lion, leopard, cheetah, spotted hyena, african wild dog… and the herbivores do thrive, at least in the protected areas where the predator-prey interactions are allowed to go on. But some 1.6 million years ago there were even MORE predator species (add at least 3 types of sabertooth cats, and a couple of large hyenas). But something happened in Africa that ended up with the carnivore guild reduced by half within a few hundred thousand years, and the key change was probably the entrance of hominids to the large predator guild with the appareance of the large and aggresive Homo erectus (“ergaster”). Neither the herbivores nor the carnivores were hit nearly so hard then as during the Megafaunal extinctions in NA, but there is evidence that hominids can create quite a disturbance in ecosystems as they enter the large carnivore guild. Wether this happens through a “trophic cascade” or not escapes me. I tend to see things more through the classic “overkill” lens, because the paleontogical record shows that the North American Quaternary carnivore guild, which may apppear crowded to our eyes, took shape during many hundreds of thousands of years during which a fine tuning between predators, prey and vegetation must have operated during countless generations, with predator control acting always as a mechanism of balance rather than one risking collapse. To add one more predator to the guild does not create the risk to “collpase the building”, unless that predator is of a totally different nature -say, human. So I think it is not a matter of having too many predator species. If humans had arrived to a North America with an already impoverished predator guild, my bet is that a Megafaunal extinction would have occurred anyway, as it happened in places like Australia which did not have an especially rich large predator guild… Anyway these are just thoughts!

  2. Well, if Australia didn’t have an especially rich large predator guild, I can certainly see the disappearance of any of those predators drastically effecting the ecosystem.

    I just read a paper entitled “Out of Asia: A Paleontological Scenario of Man and his Carnivorous Competitors in the Lower Pleistocene” that details the entrance of hominins into the predator guild of Europe. Now, in it, I encountered an anomaly that I encounter rather often in reading about Pleistocene predator guilds, which is the claim that Homotherium, in this case Homotherium crenatidens, was a predator of large prey animals such as proboscidean calves and “other pachyderms” (I assume in this case that means rhinos and hippos). The specimens it refers to seem to be much heavier than the specimens that you described in your post about the ecology of Homotherium. The same anomaly appeared in the paper I read about the “trophic cascade” model that I referenced earlier, in which Homotherium serum, the American species, was also claimed to be a specialist of large prey, such as mammoths and mastodon calves. Now, this paper about the entrance of man into the European predator guild also states the possibility that man initially entered the predator guild as a scavenger of carcasses created by Megantereon cultridens, a flesh-eating specialist, before becoming a carcass owner, at which time he would have competed with other carnivores such as bears, hyenas.

    So, in what way do you think that the entrance of hominins such as Homo erectus, Homo heidelbergensis, and neanderthals into the predator guild affected it? Did they cause a significant restructuring do you think?

    • Yes, I am sure the entrance of hominins into the predator guild did drastically affect it. But I doubt it happened in the exact way Hemmer describes it. I am not sure that large carnivores in the Pleistocene were partitioning their resources in such a very neat manner as some theroretical models propose. After all, if you look at the modern guild of carnivores in Africa you see that several carnivore species concentrate their efforts in the same few species of abundant ungulates. Populations of giant herbivores such as proboscideans are not controlled by predators today and I doubt they ever were. There is an interesting study of sabertooth bite mechanics that shows that, with all their adaptations to large gape, sabertooths only managed to clear the tips of their upper and lower canines about as much as modern big cats do, implying that the necks of the animals they preyed upon would have a similar diameter, implying generally similar sized prey. I suspect sabertooths did take giant prey a bit more often than modern cats do, but not to the extent of being specialist “pachyderm killers” and not to the extent of controlling their populations.
      But I agree with Hemmer that hominins armed with advanced weaponry carved a niche for themselves among large predators and had a severe impact on the guild. Then, as commented on the other paper you mentioned, humans had the advantage of switching to different food sources if large game was depleted, so their competition with other predators was “unfair”, so to speak…
      This is a very complex issue with almost too much room for speculation!

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