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The Mini Dinosaurs from the Harz Mountains
FiReaNGeL writes "When unusually small dinosaur fossils were found in a quarry on the northern edge of the Harz Mountains in 1998, it was initially assumed that these were the remains of a group of young dinosaurs. This was a fallacy, as the Bonn palaeontologist, Dr. Martin Sander, recently discovered. At a maximum estimated weight of one tonne, they were only a fiftieth the weight of their closest relatives, the brachiosaurs, and thus by far the smallest of the giant dinosaurs which have ever been found."
How do we explain pigme people in africa? And what is to say these hobbit people originated on the island. It could be very well be that they came ot the island after fleeing from somewere else. As evolution placed the genes in pigmes, it could be the same with the hobbit people. Once it is there, it stays until watered down by outside influences just like the pigme people in africa.
Could it be that we just don't have enough fossil or other records to even prove our current theories as fact. Sure everything points to it being this or that but what if we are missing a very large portion of the story.
Instead of the oxymoron "smallest giant", they should have said "smallest member of a family of dinosaurs whose other members are known to be giants, like the Brachiosaurus".
Nuffsaid
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Don't know about his cat, but Schroedinger is definitely dead.
Also don't forget the dwarf woolly mammoths that inhabited Wrangel island until a few thousand years ago (well in to the current interglacial).
http://en.wikipedia.org/wiki/Dwarf_mammoths
Clearly there are multiple factors at work that affect dwarfism or gigantism. It's not possible to predict the effects of living on an island for any particular kind of animal without a lot more information. This other information might include, size of island, nutritional requirements, habitat, population dynamics, behavior, climate, other animals (predators and competitors for resources), topography, behavior, and probably much, much, more.
NOTE: IANAEB (I am not an evolutionary biologist).
Not all trilobites are particularly large. Most, in fact, are about the size of today's arthropods. The main reason arthropods never get particularly big is that if they were much bigger than they are, their bodies wouldn't be able to hold their own weight. (When size doubles, strength increases by a square, but mass increases by a cube)
Interestingly enough an Adam Brumm from the Australian National University has a different take than you. He says that the tools are actually very simple and the skills to make such tools had been developed on the island for over 800,000 years.
It is amazing how many different opinions there are on the same facts:-)
reference: http://news.bbc.co.uk/1/hi/sci/tech/5021214.stm
This is a common misunderstanding in the mechanisms underlying natural selection. It is not the case that there's just one direction that things inevitably go, or even in fact that there's a definitive pressure applied by a given type of environment. It is often the case that several contradictory pressures are applied at once, and in many cases a species branches to fulfill both of them.
In fact, it's worth noting that all five of Earth's five biggest reptiles are in the setting that you suggest that they do not do well - the Crocodile Monitor from Papua New Guinea, the Komodo Dragon/Monitor Lizard from the Komodo Islands, Varanus Gigentis which lives on the islands around the coasts of Australia and New Zealand, the Goanna from Kakadu (also an island orbiting Australia) and the Water Monitor from Sumatra (the Nile Monitor is bigger than the Water Monitor, but they swim the oceans - they've been seen in Florida, Norway and Madagascar - so nobody knows where they're from, and locational pressure isn't an issue for them.) For that matter, the Butaan is in the Phillipines, and the Butaan is the only enormous tree lizard (also the only enormous herbivorous lizard) we're even aware of. And then there's Godzilla and Ghidra from Japan, Dark L'tzash "Dick Cheney" Sztsalit from Atlantis, and so on.
It is critically important to remember that speciation and trait selection are fundamentally stochaistic processes - they're _random_ , and in small populations there isn't enough buffer to clear out the mistakes. Sometimes an adaptation occurs not because of pressure, but the adaptation is so fundamentally different that it causes the ecosystem to change around it (the introduction of free oxygen through photosynthesis is the most dramatic example, but you see this gappen a lot when predators' targets are moved up and down the food chain, too.) Hell, sometimes an adaptation in Species A is a force for change in Species B. The oft-reported bit about the color of Rooks in London when industry happened, and made white birds easier to see than black birds, is frequently not followed through: there was a species of falcon which moved entirely away from brightness sight and towards motion sight, and the behavior of the rooks changed to made fewer and sharper turns to compensate.
This notion of "efficiency" isn't really that big of an issue to the reptiles; if it was, they wouldn't gorge and squat the way they do, which is tremendously inefficient (great cats do it too, except in the desert.) It is suspected that the reason some lizards shrink is to hide more effectively in an island where there isn't much room to hide. That explains neatly why it doesn't happen to the lizards that manage to stay at the top of the food chain; they just have no reason to hide in the first place. This is nicely seen in the Blackthroat and Red Acanthurus monitors, both who are from the same part of Indonesia - the Blackthroat got a thicker skin and a stronger jaw, making it the bad boy on the block, but the Red got a hide that looks like the local underbrush, shrank and got a brief turbo boost like crocodiles have.
I think it likely that the hobbits are indeed a new branch of hominids, but without a good, solid explanation for why they would be small, the theory will never be acceptable to any evolutionary scientist worth a damn, no matter how much they want it to be true
Yeah, um, wrong. Genetic historians know that not everything happens for a reason; it's a question of survival. We didn't evolve for spina bifida or kleinfelter's syndrome; it just happened. Sometimes those random things are good - eyeballs. Sometimes they're bad - mongolism. Sometimes they're a mixed bag - sickle cell anemia, which though it causes potentially fatal episodic shock, confers significant resistance to malaria, which before medicine was a pretty big win. Give those people another 50,000 years in the wild, and they'll probably develop a modified sickle cell which still fights the malaria but which doesn't clog the capillar
StoneCypher is Full of BS