Then I have another question. From what I know, evolution is less about survival from other species, but rather an internal conflict among the same species for food and mates.
Essentially, yes. One must not forget that the key to evolution is
reproduction. Considering that the biological species concept is that a species is any group of actual or potentially interbreeding populations, it is correct to consider natural selection working within species.
So the biggest challenge will, of course, be a source of food which also applies to us humans, and I believe that when people say we are to stop evolving because we have no other predators is a severe fallacy. While it is a point, I believe, from what I know, that our survival depends on how we support ourselves in our population.
Predation or not, we haven’t stopped evolving. Darwin’s observations still hold true, if not more so today. Natural resources are still finite, populations reproduce more than is supportable by the habitat, populations contain phenotypically diverse individuals all with differing Darwinian fitness, and especially for humans: population is no longer static.
We are growing almost exponentially. The natural consequence is as true as ever: We evolve!
Continuing on, there is also a critical density of population at which point the food to population ratio will tip. We will not get enough food for the people. Hypothetically speaking, that, if we do not get enough of that new technology and new food sources on our hands in time, then we will soon run out of food, right?
Particular segments of humans will run out of food. Considering the level of resource inequality in the world, us middle-class, 1st worlders have little to worry about. Can’t say the same for our brother in Mumbai or Jakarta. There’s been speculation on the cladogenetic consequences of this inequality (i.e. the possibility of species splitting). I haven’t read any academic journals concerning this, and considering the dramatically large amount of time speculated, I’m remaining skeptical on this:
news.bbc.co.uk/2/hi/uk_news/6057734.stm
So then we can assume that the critical density for that point was in the past- because we had dwindling resources but produced anyway without knowing where the critical point was- and now we face intermittent hunger.
I haven’t the slightest clue. This would be a good question for an evolutionary biologist, possibly a sociologist. I don’t know where any such “critical point” would be, I have no data, so I cannot directly answer your question. What I can tell you (in a hypothetical manner) is that this could only spell gloom and doom for part of the human family. We could theoretically see a dramatic drop in the human population (and subsequently a bottleneck in the various human gene pools) due to mass starvation. I do believe however that Global Climate Change would be a much more likely culprit than overpopulation.
Next is, from what I’ve heard, evolution less about gradual change, but sudden change at the hand of these calamities. Feel free to prove me wrong, as far as I know it’s a valid theory inside evolution (gradual and sudden).
Not necessarily. Evolution can take on either rate. There was once a rather large debate within biology over “Punctuated Equilibrium” (sudden change in the fossil record) and “Gradualism”. Most biologists today understand that these two paradigms are not mutually exclusive. We’ve since learned that things such as the bottleneck, founder effect, and populations in peripheral isolates are great at coaxing rapid, sudden, and often extremely diversifying change. With a suddenly smaller population, new (migrated to) environment, or drastic cut-off from the larger gene pool, natural selection has a much larger variety of options which naturally gives rise to sudden “punctuated equilibrium” like changes in populations. In most cases of punctuated equilibrium, we have found that a natural disaster, or founder effect was usually at play.
Where am I going with this again… oh yes, evolution. Then, therefore, it is probable that we, as a race, undergo relatively large changes, right? So basically, evolution, or?
Again, it completely depends. I would consider the Amish community a founder effect. Due to the relatively small gene pool within their actually interbreeding population, we have seen some rather large (average) changes not so exhibited in the larger American population. Polydactyly and hemophilia are much much more common in the Amish community than in any other. The phenotypic frequency of each dramatically changing in a relatively quick time.
I don’t think we can speak about “the Human Race” considering the evolution we currently witness. Just like any other species, the differing populations live in different environments, and are subject to differing selective forces. We should consider the frequency changes in particular populations and compare them to others.