New "dwarf hominid" remains discovered in Indonesia

[Ophiolite]

I think intelligence could decline in certain circumstances. If it is not being selected for then as an expensive luxury it could atrophy in the same way deep sea fish lose their eyes.

There are a mutiplicty of instances where animals have lost abilities or features that were hugely useful at one time. So' date=' I agree competely that having once developed intelligence there is no reason it should always be retained. I believe the [b']value [/b]of intelligence of a human order is still debated - what has it brought us? Global warming and Days of Our Lives.

That said, I can't see why these little guys and gals could not have been of the same close order of intelligence as ourselves. (In an earlier flippant post, the point later echoed by some others, I note that brain size is partly dependent on body mass, so that with much smaller bodies there is not a need for such a large brain.) I hope the condition of the material is such that the relative size of the different parts of the brain can be accurately detemined.

[SubJunk]

Spaceman, perhaps you could clarify for me exactly what it is about what I said that you disagree with. In detail please.

[SubJunk]

One thing though spaceman.

 

"i get by on a bag of peanuts and a nice mackrel a day"

That's nice for you, but I'm guessing you're fairly skinny, unless you've only been eating such a little amount of food recently. I'm also guessing you don't work in a very physical environment, not very sporty etc.

You must remember that humans get life handed to them on a platter, however. We don't grow up in the wild or spend most of the day hunting for food.

What I'm saying is that we don't physically exert ourselves (on a whole) as much as a wild animal would.

It's common-sense, I know, and I'm not some idiot for saying it, I just know that sometimes it's good to keep simple things in mind before you go off on complicated tangents.

[Ophiolite]

(i get by on a bag of peanuts and a nice mackrel a day)

Where do you get your vitamin C?

[Spaceman]

I hate mackrel,it was just an example that large brain size doesnt neccersarily require a huge quantity of food.I disagreed with your statement that you attributed floriensis size to malnutrition when this has no basis in fact.Also that a large brain needs huge amounts of food,when motabolism and body size is much more relevent.

 

I'm guessing you're fairly skinny' date=' unless you've only been eating such a little amount of food recently. I'm also guessing you don't work in a very physical environment, not very sporty etc.

You must remember that humans get life handed to them on a platter, however. We don't grow up in the wild or spend most of the day hunting for food.

What I'm saying is that we don't physically exert ourselves (on a whole) as much as a wild animal would.[/quote']

Are you validating your point by saying that i may be skinny thus requiring less amount of food for my brain because of my innactivity.I run half marathons!

You realise in the wild predators are not big fattys,if we were running around in a wild environment the majority of our species would be leaner not the opposite.

[Auburngirl05]

I would think that "shrinking", or evolving a smaller body size than other Homo species, would be a strategy to preserve brain power, if there is less body the brain can maintain its function on less energy, with no need to sacrifice intelligence. I honestly don't think they would have evolved into less intelligent individuals, especially if they had to rely on their wits to avoid becoming prey for komodos.

 

There have been studies done on anorexics that show significant brain shrinkage due to malnutrition, but as far as I know it doesn't significantly affect intelligence later if they recover and restore healthy physical condition. Not that it is entirely relevant when discussing evolution, just thought it was interesting to note.

[LucidDreamer]

I think intelligence could decline in certain circumstances. If it is not being selected for then as an expensive luxury it could atropy in the same way deep sea fish lose their eyes.

 

The idea of evolving a more efficent brain would be a good alternative' date=' but what redundancy are you refering to? It seems odd that homo sapiens would evolve in a wasteful way to have useless redundancy in the brain.[/quote']

I have to agree with you that in some situations man might loose intelligence, and this island may be an example of this. However, I believe there are or were Komodo dragons on the island, which would require intelligence to avoid being their dinner. Were there small elephants on the island that they hunted as well?

 

Anyway, A brain can be reduced in size yet still retain the big brain capabilities. Intelligence is not strictly related to size. I mentioned several examples in an earlier post. For another example take very small dogs. Many people claim that small dogs are actually smarter yet their brain size is reduced (I think, I couldn't get an exact conformation on this). Why couldn't a human be the same way?

 

Brain redundancy isn't as useless as it sounds. It allows people to recover or maintain brain functions after head trauma or disease. It is also a component of brain plasticity, which has many advantages. But still I think that unless Flores man experienced regular head traumas that this redundancy might be sacrificed before other more essential components of intelligence. I couldn’t find any good sources on redundancy for some reason, but here are the ones I managed to get:

 

http://peace.saumag.edu/faculty/Kardas/Courses/GPWeiten/C3BioBases/BrainOrg.html

http://www.headinjurylaw.com/brainreorg.htm

http://www.scism.sbu.ac.uk/inmandw/review/cogpsy/review/rev6768.html

[Auburngirl05]

Intelligence is not strictly related to size. I mentioned several examples in an earlier post. For another example take very small dogs. Many people claim that small dogs are actually smarter yet their brain size is reduced (I think' date=' I couldn't get an exact conformation on this). [/quote']

 

Remember that reduced brain size in dog breeds would result in relatively constant body/brain ratio, meaning even normal intelligence in a smaller brained chihuahua shouldn't be surprising. True, that ratio does not always indicate intelligence, but small dogs are not considered to be smarter in general, on a widely accepted ranking list only two of the top ten breeds are under 45 pounds when mature. http://www.petrix.com/dogint/1-10.html Most working (aka thinking) breeds tend to be at least medium sized, with some exceptions, and I would assume their brains differ in important ways besides size from similar sized or even larger breeds with lower intelligence.

 

One interesting and entirely irrelevant note: eyeball size is constant in all dog breeds, from Danes to Yorkies. (I work for a vet and am full of useless info on dogs, lol)

[Auburngirl05]

Now that I think about it, though, dog breeds probably don't have much value as far as evolutionary fitness goes, the vast majority are semi-mutants thanks to humans' fascination with anatomical oddities, lol...

[Spaceman]

Now that I think about it, though, dog breeds probably don't have much value as far as evolutionary fitness goes, the vast majority are semi-mutants thanks to humans' fascination with anatomical oddities, lol...

Dont undermine your own ideas,i think you put yourself across quiet well

[SubJunk]

Spaceman, there's a difference between being skinny and having lean muscle.

"Nature is full of mammals — deer, squirrels and pigs, for example — living in marginal, isolated environments that gradually dwarf when food isn’t plentiful and predators aren’t threatening."

http://msnbc.msn.com/id/6346939/ there's a source

[Spaceman]

I totally agree with your first line,thats why my posts disagreed with yours(post 53 etc)

thankyou for your example link,which by the way was as much use as a chocolate fireguard(please dont take offence)

but what has post 61 got to do with your original post on the subject.Alligators in the florida swamps have been the same for millenia im sure you will agree that they are living in a marginal,isolated environment.Have they shrunk or atrophied(is that how you spell it)please no need for a reply but what has your post got to do with your earlier assumptions of our midget friends the eight dwarves

[DreamLord]

Well, first alligators ARE the predators. So they need to stay rather large to go hunt food.

 

I dunno about the predator thing, but... about creatures living in areas where food isn't readily available. Evolution would make them smaller. I can see how that would work. Like how many desert animals tend to be rather small compared to say, animals living in plains or forests.

[Spaceman]

Well' date=' first alligators ARE the predators. So they need to stay rather large to go hunt food.

[/quote']

Eh !!!!Ants are predators,so are ladybirds.And yes so are killer whales,size of a creature has nothing to do with its surrounding environment.If the environment is too harsh obviously they are less creatures to fill the niche.

and before anyone wants to jump on that statement read some literature on dinosaurs,

[Aardvark]

It's a well observed phenomenon that creatures on isolated islands tend to evolve to a smaller size.

 

Remains of Dwarf Mammoths have been found on the Californian Channel islands and on Wrangel island off the coast of Siberia.

 

It's a matter of genetic adaptation, not malnutrition.

 

Curiously the human inhabitants of the British channel islands tend to be quite short. Probably just a coincidence but interesting.

[LucidDreamer]

The issue here is island dwarfing, which primarily deals with large herbivorous mammals living on islands that tend to shrink in size over the generations.

 

opps, you beat me to it.

[DreamLord]

Eh !!!!Ants are predators,so are ladybirds.And yes so are killer whales,size of a creature has nothing to do with its surrounding environment.If the environment is too harsh obviously they are less creatures to fill the niche.and before anyone wants to jump on that statement read some literature on dinosaurs,

 

As it's been said before most of the time it is the herbivores that shrink when living in a more isolated environment. And granted, environment does not always play a part in the size of a creature, but it can. As I said, desert animals tend to be smaller because there is not enough food in the desert. Where as many plains animals are larger because the abundance of food. Buffolos, Elephants, and giraffes would be an example. Girrafes being so large because they had to reach the top of the trees, there aren't really any large trees in the desert, so therefore no need for tall animals there.

[Spaceman]

The issue here is island dwarfing' date=' which primarily deals with large herbivorous mammals living on islands that tend to shrink in size over the generations.

 

opps, you beat me to it.[/quote']

haha excellent post lucid,the thread needed that.

Bear in mind lads the komodo dragon which has been mentioned here inhabits small islands and has done for millenia,i think its quite large and seeing how its main diet them little guys died out 20 or so thousand years ago shouldnt it be the size of a newt

[Auburngirl05]

Can the dwarfing principle be applied to ectothermic animals with that have indeterminate growth (ones that never stop growing, such as many types of reptiles: gators, turtles, anacondas, etc)? I'm not being rhetorical, honest question.

I would think that it wouldn't apply, seeing as how huge monitors and of course komodos thrive on islands, although that could also be explained alternatively because the predator role obviously provides them with a better quality of food than a hunter/gatherer would rely on.

But that factor comes into play when discussing crocodiles and alligators....and I honestly don't know enough about reptiles to know the degree of indeterminate growth various reptiles can have, obviously some grow to consistently larger sizes than other species do...any insights from someone more not as reptile-illiterate as I am?

[Auburngirl05]

Sorry that parts of my above post repeat others, I think I was posting at the same time as a couple of other members, who obviously have faster fingers than me.

[Sayonara]

It's a well observed phenomenon that creatures on isolated islands tend to evolve to a smaller size.

 

Remains of Dwarf Mammoths have been found on the Californian Channel islands and on Wrangel island off the coast of Siberia.

 

It's a matter of genetic adaptation' date=' not malnutrition.[/quote']

Counter-examples:

Galapagos giant tortoise and the Komodo Dragon.

 

What are the causes and mechanisms for this genetic adaptation you are speaking of?

[Sayonara]

Alligators in the florida swamps have been the same for millenia im sure you will agree that they are living in a marginal,isolated environment.Have they shrunk or atrophied(is that how you spell it)

Yes, they have, although you can shrink the timescale down so far that it looks like they have not.

 

 

size of a creature has nothing to do with its surrounding environment.If the environment is too harsh obviously they are less creatures to fill the niche.

and before anyone wants to jump on that statement read some literature on dinosaurs' date='[/quote']

What exactly does that mean? A niche is not volume-dependent, it's the abstract description of the availability of a community task set.

 

 

As it's been said before most of the time it is the herbivores that shrink when living in a more isolated environment. And granted, environment does not always play a part in the size of a creature, but it can. As I said, desert animals tend to be smaller because there is not enough food in the desert. Where as many plains animals are larger because the abundance of food. Buffolos, Elephants, and giraffes would be an example. Girrafes being so large because they had to reach the top of the trees, there aren't really any large trees in the desert, so therefore no need for tall animals there.

Don't forget the survival advantages that are gained by being big. Although I don't agree with everything that has been said in this discussion so far, it is true that size does not just come down to food (or any other single factor).

[Ophiolite]

Curiously the human inhabitants of the British channel islands tend to be quite short. Probably just a coincidence but interesting.

It could make a fascinating doctoral study. Of course the downside is that you would have to visit places like the Bahamas' date=' the Seychelles, the Maldives and Fiji for your field work.[img']http://www.scienceforums.net/forums/images/icons/icon7.gif[/img]

[Severian]

Has it been proven (genetically) that it is genuinly a different species? I had always thought that there were tribes of pygmies in South America. Why is this not just a slightly more extreme example?

[LucidDreamer]

They are currently trying to extract DNA, but it has not been proven genetically where exactly Flores Man fits in. However, there are a number of structural differences of Flores Man that do not match any species. The most dramatic difference is the cranium size, which would only allow for a brain about 1/3 the size of our own.

 

Brain volume (cm3) Avg body mass (kg) Brain vol / body mass (cm3/kg)

Pan paniscus 343 35 9,8

Pan troglodytes 395 45 8,8

Gorilla 505 105 4,8

A. africanus 420 36 11,7

P. robustus 502 36 13,9

H. ergaster 804 58 13,9

H. erectus 950 57 16,7

H. neanderthalensis 1512 76 19.9

H. sapiens (overall) 1350 53 25,5

H. sapiens (Pygmy) 900 30 30,0

H. floresiensis 380 30 12.6

 

http://redrival.com/evolusi/humevol5.htm

http://pharyngula.org/index/weblog/comments/homo_floresiensis