Monday, August 25, 2008
Walking with Prehistoric Beasts
Walking with Prehistoric Beasts continues where walking with dinosaurs left off and tells about some of the creatures who lived from around 65 million years ago (really though it's more so 49 million years ago, I don't know why they skipped the Paleocene age) until around 30,000 years ago. This was a very well done documentary, the CGI and movement were better than Walking with Dinosaurs, though it wasn't bad in that series either.
For some reason this period of time just doesn't get the type of attention and awe of the dinosaurs. I don't know why, the biggest known creatures of all time come from this time. True they are in the ocean and the biggest one known of all time is still around today (Blue Whale). The land animals may not have been quite as big as the dinosaurs but they were still very large. Sabertooth cats and Indricothere were very, very large. They also have a seemingly larger variety of body types. We also know a lot more about some these large creatures than we do the Dinosaurs. The Woolly-Rhinos and Woolly-Mammoths lived along side humans for awhile and we have found their remains in incredible detail. Some of them are so well preserved in ice that the meat could theoretically still be eaten (which makes me wonder how much a mammoth steak would cost).
It mentions that 49 million years ago bird ruled the world. Particularly large flightless meat eating birds. These large "terror birds" really aren't that different from dinosaurs. Some dinosaurs like ornithomimid's had bird like beaks made from keratin like modern day birds. Some dinosaurs had feathers, though some scientists (a minority) do argue this stating that they aren't feathers instead they are "structural fibers, probably collagen—the most abundant fiber in vertebrates—of the skin and the dorsal frill" and that birds did not evolve from dinosaurs instead they share a common ancestor. I have no reason to disagree with the majority of paleontologists who claim to have a lot of information pointing to birds being direct descendants of the dinosaurs. I suppose it is possible that they did evolve separately from a common ancestor but even if that is true, that doesn't necessarily mean dinosaurs couldn't have had feathers. Two parallel evolutionary paths could have many similarities. The thing is dinosaurs like oviraptors, a particularly bird like dinosaur with a beak and feathers, look very similar to the large flightless bird of the time after the dinosaurs and those large flightless birds could possibly have evolved from them. This class of dinosaurs was generally small but they have found remains in China of a 26 feet long and 16-1/2 feet tall bird-like dinosaur that lived around 70 million years ago called Gigantoraptor erlianensis (36 times larger than the nearest known relative).
Mentions some of the animals date of extinction like the Woolly Mammoth. It says they died out 19,000 years ago. Newer findings contradict that. In Europe and Southern Siberia some were still present until about 8,000 BC. A small population of woolly mammoths survived on St. Paul Island, Alaska, up until 6000 BC, while another remained on Wrangel Island, located in the Arctic Ocean, up until 1700 BC. Though these island living ones that died out much later are a dwarf variety. Other dates given for animal extinctions have also been revised since some small populations of the various animals have been found to exist for longer than originally thought.
There are Australopithecus in the series and they say that they are an ancestor of modern humans. This was thought for a while but recent studies (2006) have changed some scientists minds since it's jawbone is closer to a gorilla's and creatures from the genus homo (our genus) have been found that date further back than Australopithecus, so the branching of the family tree was earlier. Its still part of the Human clade (had a common ancestor of us) but we're not direct descendants of them.
In the making of video entitled Triumph of the Beasts, one person states that the creatures are so weird looking. Personally I did not find them to be very weird looking. A lot of the animals have similar looking animals still alive today. A woolly Mammoth and woolly Rhino really doesn't look much different than the non-woolly versions. There are far stranger looking creatures in existence today and creatures that seemingly make absolutely no sense. A Platypus for example is a very strange very weird looking creature. It is an egg-laying, venomous, duck-billed, beaver-tailed, otter-footed mammal that walks like a reptile. Personally I find platypus (there is no real plural form for them and several different ones are used) to be the weirdest thing, even genetically they are weird having 10 sex chromosomes and we have no idea at all how the sex is determined since it doesn't have the SRY gene that most mammals have and seems that it sex genes might be similar to birds. A study of the platypus genome sequence revealed it to have both reptilian and mammalian elements, as well as two genes found previously only in birds, amphibians and fish. If you want to see things that truly look alien magnify microscopic insects and look at the creatures at the bottom of the ocean.
In the second making of video entitled The Beasts Within, One of the people states "from what we know about human evolution upright walking came before tool usage". I don't agree with that. I say this because there are living primates who do not walk upright that use tools on occasion. Wild monkeys have been observed using thrown branches to discourage threatening or pursuing individuals; wiping of wounds with lightly masticated leaves; thrown rocks; sticks used for clubbing, throwing, prodding, prying lids, and to reach objects and rake them in; and rocks for pounding upon tough fruits or nuts. Monkeys have also been observed playing with sticks and helping each other with tools - wiping other monkeys wounds. Chimpanzees use containers, have been observed in captivity to store water and they use anything from leaves to rope as a sponge to draw water when they can't reach it then suck on it to get the water. They will fish for termites, dip for ants, pick locks, use sticks to touch things that they prefer to avoid (dangerous or unpleasant objects/animals or new chimps), use poles for balancing and climbing, and clean themselves with leaves. Recently (2007) chimpanzees in the Fongoli savannah have been observed using sharpened sticks as spears when hunting (Washington Post article on this). Orangutans have also been known to braid "straws" into ropes to climb and swing and they will remove inefficient aspects of their tools, such as leaves upon a digging stick. Primates are not the only tool using animals. Dolphins have been seen using rocks to break open shells, Crows will use sticks to get insects out of holes, elephants will use sticks to scratch themselves, etc. Judging by the varied tool use of other primates that do not walk upright and animals that aren't even primates, I find it unlikely in the extreme that walking upright came first. The thing that annoys me is not so much the assumption that walking upright came first it is that these behavior in animals were observed a long time before this series was made. Example these books first one written in 1980 and second one written in 1993 document animal tool use; Animal Tool Behavior: The Use and Manufacture of Tools by Animals & The Use of Tools by Human and Non-human Primates.