I think it's fair to say that evolution of mankind ended when people mastered their environment as you put it. Evolution is a very long, gradual process taking millions of years, and the selective pressure comes from the environment.
Yes there are still some selective pressures on lions, but not natural ones. Human ones. So theoretically we are actually breeding them, even in the wild, simply by exerting our power on their environment.
Well, strictly speaking, evolution
never ends. Humans continue to evolve, to this day. What you get are periods of little change, followed by short bursts of dramatic change, driven by environmental pressure.
But the point is that without this, lions would have no great reason to evolve superior intelligence. They are apex predators, and face few threats that intelligence will aid them with. Drought maybe, deforestation, loss of habitat and prey, and sometimes being hunted.
That's not how evolution works. It doesn't function from need. Any animal
would benefit from greater intelligence. That's just a fact. If nothing else they compete with each other, and the smarter one is going to win. There is no wild animal on the planet that survives so comfortably it couldn't improve its lot.
The question really, is whether they
can evolve greater intelligence. If they can, they will. The problem is, they can't,
in their current form. Their existing physiology prevents it.
By comparison ancient hominids were not apex predators. They suffered from predation as well as everything else, and they needed an edge. Intelligence was that edge.
Humans were apex predators
long before we developed advanced intelligence.
There are many reasons why intelligence was good for them, the social evolution is the one that I find most compelling, that intelligence allowed them to form tribes and communicate, and that tribes survived better than individuals, and that those within the tribe who survived best were those who had the social intelligence to find good niches. They got the females more, stayed out of fights more etc.
I think it's more a case that the intelligence grew out of group behaviour and communication (along with tool manufacture). Remember, intelligence came last.
With lions compared with the other large cats, they are the only ones to form prides, which requires a larger degree of social intelligence than say that of the solitary big cats such as tigers and panthers. So to a certain extent they have evolved along this line already. But the question that you have to ask in looking at this question is - is there any reason to believe that the advantage conferred by increased intelligence going to aid them more than it costs them?
If it costs them more than it benefits them, by definition it can't happen. That's how evolution works.
Don't forget, higher intelligence, bigger brains as a rule.
It's not really that simple. While a minimum brain size is necessary for the complexity of higher intelligence, the crucial thing is really brain size relative to overall body size. Modern human heads aren't any bigger than our ancestors - in fact our brains are smaller.
If we hypothetically imagine lions started to develop higher intelligence, you'd probably find over time that their bone structure and general muscle mass would slowly decrease, as it has with humans. They would increasingly rely on their greater intelligence to overcome problems rather than brute strength.
And of course the brain requires additional calories to run. So if we look purely at the social intelligence side of things, will the advantages of increased intelligence allowing them to form larger tribes instead of prides, outweigh the disadvantages, and generally I see no reason why it would for them, or any other apex predator.
It would give them an advantage on a number of counts. For one, they'd be better hunters. Lions, like most predators, struggle to catch enough prey to survive, and starvation is a constant threat. Probably the biggest threat to most wild animals, however, is their own environment. Greater intelligence allows for greater awareness and understanding of the environment, drastically improving an animal's chance of survival.
Sharks are another apex predator that has no reason to evolve advanced intelligence. They have swum the oceans for hundreds of millions of years, essentially unchanged, simply because they are already supremely adapted to the environment (until we came along of course).
Again this just isn't true. Aside from having a number of predators (killer whales and dolphins, for example), sharks could likewise benefit from greater intelligence if just by being better predators.
As I see it, you and some others have made the argument that many animals
could evolve greater intelligence, if it were of benefit.
My problem with this logic is that animals can
only evolve traits that are of benefit to them.
By definition evolution involves the beneficial change of species over time. Thus, if you accept that the changes necessary for higher intelligence would be harmful to an animal, you're essentially acknowledging that it's impossible for said animal to evolve intelligence.
Thus we're back to the original argument, that intelligence only develops in specific circumstances.
I agree with you completely by the way about what evolution of superior intelligence leading to a sapient species would entail. Tool using, communications and problem solving. Any alien space travelling sentience would have to have these traits.
None of those are really traits specific to higher intelligence. Virtually all animals communicate, and many animals use tools and have problem solving abilities.
However, there is no reason to assume that they would have to follow a hominid body plan to have them.
I disagree. Unless, of course, our understanding of physics and chemistry is fundamentally wrong.
Octopi and apes can both use tools. Elephants if you've ever seen them grab a branch and scratch their backs with it are on the path. Hell even otters have mastered some tool use.
None of them is capable of
manufacturing tools (i.e. forming tools from two or more disparate objects), and none of them displays permanent ownership of tools. It's opportunistic behaviour.
Humans were making
permanent tools long before we were particularly intelligent. It seems to have been a crucial catalyst for intelligence.
Some apes could probably get there, under the right conditions. Chimpanzees and Bonobos are by far the best candidates, but it would require something quite extraordinary such as the very gradual deforestation of the Congo, forcing them to towards bipedalism (such an event seems highly improbable).
Octopi have virtually no chance of developing high intelligence. For one, they have a decentralised nervous system. High intelligence requires the very opposite. But perhaps more importantly the underwater environment simply isn't energy-rich enough to support advanced brain power. I also can't think of how or why they'd develop greater dexterity, given their underwater environment.
Both elephants and otters are eons (literally) away from developing pairs of limbs with the dexterity necessary for tool manufacture - the elephant more so of course given its physiology. you have to ask yourself what sort of environmental pressures would push elephants or otters to develop limbs with strong clasping appendages (i.e. hands) on the end? Then you've got to reverse those environmental pressures so the clasping appendages become unnecessary, and are free to be applied to full time tool use.
And even if all that happened, you'd end up with a humanoid otter or elephant creature.
