Take dolphins

Land based mammals who moved back into the oceans, I don't think that counts.

-*how do you spell -plural octopus- anyway?

http://grammarist.com/usage/octopi-octopuses/

Take dolphins or the various species of octopus for example (especially *octopi, arguably, some species are even more intelligent than humans)

So how intelligent are octopi?  I've seen them compared to dogs, i.e. a mammal, which is exceptional for sea life apart from mammals (like dolphins).  So why do we have so many relatively intelligent land creatures like mammals, and not so many animals which developed such intelligence in the sea (excluding sea mammals, which were land creatures).

midtskogen, by your definition, its possible the answer is bigger brains and/or brains at all. Take coral for instance. Meanwhile, here on land, animals have developed more complex brains for solving more complex problems with their environments.

here on land, animals have developed more complex brains for solving more complex problems with their environments.

Which is exactly what we are pointing out.  The ocean does not seem to favor big brains.

Considering the short time available to them to gather knowledge and experience, octopuses may be one of the most intelligent species at all.

The ocean does not seem to favor big brains.

This may be true, but why?

midtskogen, well on land, you have obstacles such as trees, rocks, streams, cliffs, etc. But in the ocean, creatures don't really have these obstacles unless they live near the seafloor (like octopi).

but why?

Probably a case of if I knew that I would have a nobel prize in biology waiting for me

well on land, you have obstacles such as trees, rocks, streams, cliffs, etc. But in the ocean, creatures don't really have these obstacles unless they live near the seafloor (like octopi).

Big brains are also very expensive to grow and maintain, you may need a bit more than just a complex environment. High energy food sources, access to plentiful oxygen, and plenty of other things to factor in. Dolphin's and other ocean mammals have an advantage from their ability to breathe concentrated oxygen to help power their large muscles, circulatory system, and big brains.

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DoctorOfSpace, nice video! But wouldn't preventing aging lead to a population boom, which could lead to overpopulation?

Also i found some videos that i think relates to the future of mankind, by an rapidly growing channel No guarentee of this being related in any way whatsoever to the topic.
[youtube]uGtWnH7mQBQ[/youtube]
[youtube]b44yxy1MzJs[/youtube]
And some Kurzgesagt videos:
[youtube]jAhjPd4uNFY[/youtube]
[youtube]ZL4yYHdDSWs[/youtube]

But wouldn't preventing aging lead to a population boom, which could lead to overpopulation?

But wouldn't curing heart disease, strokes, bacterial infections, genetic disorders, and any other disease as well?  It is a non issue, the pros are greater than the cons.  More minds is a faster advance in technology and a faster solving of problems.  We need a bigger population if we ever want to start spreading into space.

Yeah, and empirically it seems that people with better quality of life tend to have fewer children.

Also that population boom was addressed in the video, fairly early on as I recall.
Currently the global human population is growing at a steady rate of one billion people every so many years. Many people are born, and many other people die, but the death rate is much smaller than the birth rate.
If nobody died (which wouldn't be the case anyway, as people commonly die of things other than old age) for a generation, many people would be born, but not more people than would be born anyway. So the mitigation on population growth from people dying would be greatly reduced, and the population would grow faster, but that simply means the number of years until the next billion people is somewhat less.
The population won't "boom" over any kind of short period and the change in population growth wouldn't significantly affect the total population for roughly a whole generation if not several.

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