Mammals going back to the water evolve bigger brains- why?

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Dr Lou Natic

Unnecessary Surgeon
Registered Senior Member
Anyone have any ideas?
Anyone think this is not the case?
If so, how can you deny the facts?

Polar bears basically are a marine mammal or are at least at the stage of turning into one. They swim for miles in the open ocean and hunt other marine mammals. They happen to be the most intelligent in the bear family. I can see how this is required. They need alot of brains to locate and sneak up on seal colonies resting on remote ice bergs. Other bears have it easy in comparison.

But what about whales? Do they really need all that intelligence? In particular baleen whales, all they really need to do is swim around with their mouths open. They have alot of left over brain power that is not required for their survival, this can be seen by the way they have made up dances and songs.

Now this is something I can't wait to have answered, which came first? Toothed whales or baleen?
If, as I suspect, the answer is toothed whales than I think that explains the left over intelligence of the baleens and I think it might give indications of how humans could have ended up with "too much" intelligence.

The transition from land to water was a big ask for the whales ancestors and they would have faced lots of trying times. Alot like the polar bear. The most intelligent members would be the ones that made it, being able to think of better ways to get food, impressing females more than their piers.

If toothed whales were first they were hunters and intelligence is always beneficial for hunters, tough times would mean small numbers with only the brainy being able to survive.

So you can see how they would get more intelligent over time. Eventually whales developed baleen(I hope, or my theories a load of bs) learning to feed on plankton which was more than plentiful. They got on easy street and joined the mindless plankton eaters. Plankton eaters who evolved eating plankton and so needed no great wit, but the whales history was more complex, it used to need its brain but now it doesn't, it just enjoys it, dreaming and telling stories and singing songs etc.

Sounds like someone we know....
humans don't need their massive brain for survival right now. So what must our history have really been like to develop it? Now all apes are pretty smart because physically they aren't as equipped as say... a lion. They have brains suitable for their needs. But what needs must we used to have had to develop a brain even bigger than theirs?
The aquatic ape theory is good for this reason I believe.

The ocean is a harsh mistress as they say. Its inhabitants can move easily when weather goes awry and this leaves a land animal relying on the ocean for food, up shit creek. I think our ancestors must have experienced some very hard times where only the intelligent made it through.

Like the baleen whales we found a backroad to easy street and now we have this big mass of unnecassarry brain left over.
Make sense?
 
The most common theory I've heard is: Social groups are similar to the great apes and hence the selction for larger brains. Same as apes (not that we know for sure why apes have larger brains).
 
On land big brains come at a big cost. They are extra bulk that needs to be supported and they produce a lot of heat. Water supports the extra weight and helps carry away excess heat.

Just my thoughts on the subject.
 
my little though for today

The ancestors of aquatic mammals were used to a certain perceptual richness of their world. Maybe to achieve the same richness underwater you need more computing power and hence a larger brain.
 
Lets see if you were 10-30meters tall I bet you brain would be pretty big as well! Usually the bigger you are the smaller the size limit on you brain. It not proportional to size though: a 10meter tall dinosaur only had a brain twice the weight of its 2meter counterpart. A Whales brain is pretty small compare to its weight and size if you think about it. If there is one thing humans have above all other animals its the largest brain weight per body weight ratio... if you look at our history and current motives though: our brain size it not something to be proud of!
 
Maybe it is easier to figure out the theory of relativity or write a symphony under water? Lets just face the obvious. There are no adaptive reasons why our species evolved such intelligence. My theory may sound a little crazy but not as crazy as some of the suggestions I have just read.

If our consciousness is the reproductive cell of a higher species then this explains the evolution of intelligence.
 
I don't think you read my post at all.
There IS some reason mammals going back to the sea develop large brain.
Is it a coincidence that polar bears are the smartest bears and that whales and dolphins are alot smarter than their ancestors?
There are lots of indications that humans started to develop for marine life and that just makes one think if you ask me.
I think its hard to deny there is some tie between the water and mammals developing larger brains. I'm not sure what it is, but its all around you.

And wellcookedfetus whales brains are very much large even in comparison to their size. Some have PROPORTIONATELY larger brains than humans. Thats PROPORTIONATELY. This is well documented.

The main point of my (unread) post was humans must have had a difficult history to develop those large brains.
I THINK human society is the product of a creature who stopped needing its large brain for survival, this left over a large amount of brain power and thus strange behaviours started showing up.
Baleen whales had a parallel history in that their ancestors required those large brains for survival, the physical development of baleen itself made this large brain unnecasarry and again strange behaviours started appearing with ritualistic songs and dances.
Come on, someone has to see that marine mammals are smarter than most:confused:
 
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I made that post a bit too quickly, I forgot some of the main points.
Baleen whales' brains have actually gotten proportionately smaller than their toothed cousins. I see a connection to the way baleen has made their lives easier. They still have huge brains but I think they have gotten smaller because they don't need them. Toothed whales still need their large brains because they actively hunt and it is only getting more difficult for them. They might evolve larger brains still because the less intelligent ones won't make it.
I think human brains would have started getting smaller IF we never came up with our society that disallows serious evolutionary changes. We came up with that society BECAUSE we had left over, unnecassarry brain power. We had unnecassarry brain power left over because we made a transition from requiring those brains to survive through hard times to not requiring them when life got easy after we eliminated those difficulties.
Pretty interesting if I am correct.

Originally posted by Robert Jameson
If our consciousness is the reproductive cell of a higher species then this explains the evolution of intelligence.
Click to expand...
But my theory actually explains our large brains while yours makes an outlandish magical assumption:rolleyes:
 
Quote from Dr Lou Natic

But my theory actually explains our large brains while yours makes an outlandish magical assumption

But polar bears can not understand the theory of relativity or write a symphony. There had to be some other factor that drove our intelligence to this far higher level. You are trying to find an adaptive reason for greater intelligence when all the costs of evolving a larger brain would have far outweighed any slight advantages of increased intelligence. Our far less intelligent primate relatives have little trouble making a living hunting and gathering with a smaller brain.
 
Maybe Dolphins and Porpoise’s brains have a high proportion ratio to there mass, but not whale brains which are only bigger then our by 2-3times in mass yet are tiny in comparison to there body mass. Have you ever seen a Blue Whales Brain it about the size of a beach ball (.4m diameter)
 
You are correct WCF.
I am arguing the large baleen whales brains started to shrink because they developed simpler lifestyles. They still haven't shrunk "enough" because we can see they have left over brain power by the way they indulge in "extra curricular" activities.

Originally posted by Robert Jameson
But polar bears can not understand the theory of relativity or write a symphony. There had to be some other factor that drove our intelligence to this far higher level.
Click to expand...
Polar bears evolved from bears and we evolved from apes. We had a higher starting point. The point is it appears the water made both of us more intelligent somehow.
I think the correllation is marine life is difficult for mammals. Evolving to adapt to this vastly different environment demands increased intelligence.
Imagine 2 people stranded on a desert island, one is an idiot and one is very intelligent. I have my money on the intelligent one surviving longest. With our ancestors only the intelligent would have survived to breed. Thus increasing our intelligence over generations. Eventually we got smart enough to make life easy for ourselves. We still had these massive brains but we no longer required them. Symphonies and theories about relativity stemmed from that.
Understand now?
 
Well I guess diving deep for squid doesn't require that much brain. Makes sense. Anything that specialised is bound to develop a brain equally as specialised. Its the animals like killer whales that need the really big brains because of their diverse menu's and life styles.
 
You are right, I studied a bit about it today.
Except that page you linked to gives some strange numbers I don't agree with.
A sperm whale weighs more than a killer whale and a dolphins brain weighs 1700 grams not 840.
Also, if we were to go on proportion to size alone a mouse would have a larger brain than a man. There are alot of factors, and whales aren't as far from humans as you think. Anyway, there is a different thread for this.

This is supposed to be about mammals returning to the water developing larger brains which I still will defend. It doesn't matter if whales have slightly smaller brains than I thought, the large whales evolved from smaller whales that had very large brains. As they got larger their brains started to proportionately "shrink" but the fact remains that their ancestors developed large brains for some reason.
Why do you think that is?
I think the transition from land to water would have demanded that only more intelligent members made it.
 
Depends on the dolphin. Do seals have larger brains in compression to say wolfs? I don’t see any connection in larger brains size being needed in evolving back into a aquatic environment. The aquatic ape theory does a better job explaining why we walk upright, why we have very little body hair and other quirks of our biology, Brain size though is better explained by becoming carnivorous and making tools and societies.
 
Seals are the only weak link in my theory.
No I don't think they are any smarter than wolves.

But I find it odd you think becoming carnivorous, building tools and making societies is what made our brains bigger. How would that happen? I argue that those things(the tools and society part anyway) are a product of us having "left over" intelligence. I think at some stage we needed these large brains for basic survival. This could have happened if alot of human ancestors were dying due to harsh conditions and only the very intelligent could think of ways to live through them. Over time this would make larger more complex brains.
Eventually conditions became easier and we didn't need the brains anymore, tools started getting more complex and free time for thinking and wondering lead to societies.
I don't see why societies would make a species evolve larger brains. It seems to stop the evolution process altogether and if it didn't I would assume it would make the brains start evolving smaller due to the fact it doesn't take intelligence to actually survive in a society. It is easy living.
This is why large baleen whales started evolving smaller brains because its alot easier to hunt plankton than it is to hunt seals.
Its alot easier to hunt farm animals than wild ones. So society would not increase a species brain mass I don't think.
 
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