We tend to have an antropocentric view on the nature, which frequently fails us. A female canguroo being chased by the dogs throws them her cub in order to escape while they are chewing on her cub. The nature's rationale is that the canguroo cubs are born just 1 cm long, and for a very long time they cannot survive on their own. If she will sucrifice herself then both will die. Meanwhile the mom can have another cub to assure the species survival. Female spiders and scorpios eat their male mates in the end of the honey moon, and the males actively provoke this outcome because well fed female is more likely to nurture successfully their offspring. If the food is scarce, then female spider might let her offspring to eat her. Whatever it takes to survive– that's the mother nature's moral code. That's how self-regulated processes with the feed back loop work in the natural selection.
III. The biological paradigm of humaniti
For those of my readers who don't believe in the evolution I suggest skeeping this chapter.
We are the end-product of 4.5 billion year of evolution, of the natural selection, and we must accept ourlseves for what we are and deal with that. No crap like "We should be.. we ought to be.. we will be" doesn't change a thing: we are what we are. Deal with this, all kinds of totalitarian "sheppards", "social engineers", "behavior modificators", "new humans builders" and all kinds of crooks, that want us to be and to do what they want. No way.
Human evolution is a puzzle that is not complete yet although we do know already the key points of the evolution with reasonable probability. As I mentioned, our single cell ancestors formed a very successful symbiosis with mitochondria life form that still give us the energy source. Our eyes gene is almost identical copy of the seaworm eye gene that "invented" eyes about 200 million year ago. Asteroid catastrophe gave the spines structure to the descendant life forms. From the remote lemur-like ancestors we have left the dreams about falling from the hights. 8 million years ago our ancestor apes in East Africa had a tooth for the nuts that had realtively high calories content, which allowed more free time allocation for the thinking and inventions such as tools. About 1.6 million year ago drier climate forced our ancestors from the woods into savannahs with consequent evolutional pressure for longer limbs. Bipedal locomotion increased horizon, improved energy efficiency and speed, although caused low back pain (just like saber-tooth tigers suffered from low back pain) as we started having bigger impact on our spines ; accelerated osteoarthritis and chronic sinus problem: the sinus draining opening is in the middle of the anterior wall, which in the quadripod face-down position is the lowest point that drains the whole sinus, while in the vertical position it drains only upper half of the sinus. If you have maxillar sinusitis, you can lie face down, which allows the whole sinus to be drained, but if it is not enough then ENT surgeon might make a hole in the lower wall because in the vertical position it is the lowest point. Again, the nature doesn't takes us apart and re-builds a new man– no, it is very conservative, it finds compromise and builds new floors on top of the existing ones.
First they used stone tools to break bones of the carcasses of the stronger predator's kill in order to obtain the bone marrow. which, again, due to its nigh nutritional value allowed to have much more for the creative purposes.
Gradually about 1.6 million years ago pro-humans started hunting big game themselves although they had to do so under the scorching sun when respected predators had a nap since the humans were no match against serious predators: number 15 amongst predators as runners, lousy smell sense, week nails and jaws, bad night vision. Noon hunting under scorching African sun exerted natural selection pressure towards several adjustments: 1) Longer limbs to run faster and longer; 2) curly hair to protect the brain against over-heat; 3) larger brain that had a lot of spare neurons to function when the rate of neuronal loss increased (normally we lose a thousand neurons a second out of 5 billion of them in the cortex, but in the heat the loss rate is much higher). Larger brain meant more axon-dendrite synapses, more elaborated neuronal information net, which resulted in a smarter brain. So, our mental capabilities are accidental byproduct of hunting during the hot time.
4) loss of body fur that eased the cooling during the hunt by removing excessive insulation; 5) increse in the amount of eccrine sweating glands to cool down the body during motion.
Unintended conseqences were: 1) decreased tolerance to cold (which later was compensated by using the clothing and by discovery of fire); 2) minimized opportunities for previous communication ways such as rising fur, which exerted selection pressure to develop other means of communication, such as facial mimic musculature development, speech and skin coloring/tatooing; 3) risk of skin cancer due to the loss of protection by fur, which was compensated about 1.2 mln y.a. by dark skin MC1R mutation. 4) loss of camouflage function of the fur => skin painting/cloth use.
Originally the skin under the fur was gray and pink, after the skin mutation it became dark, when some humans migrated to Asia it got lighter, when some migrated to Europe it became white to absorb UV ray to produce vitamin D. The problem in Africa was too much sun, so the pigment melanin in upper layers of the skin shielded deeper skin. The problem in cold Europe was the lack of sun: cloudy days, warm clothing, long time in a shelter. Children during growth spurt need vitamin D for the bone and skin growth, so the selection pressure was to have very fair skin during 1st 2 years of life (unless drinking vitamin D fortified milk, Europeans need 10 minutes a day sunbathing to produce enough vit. D while blacks need 2 hours. If there would be no vit. D in milk, Afro-Americans in some time would become fair skinned too). When Arian tribes migrated to India from Europe, the natural selection started working in reverse– Hindus have darker skin because those from offspring with darker skin due to natural variability were more likely to avoid skin cancer. Right now Australians have highest in the world skin cancer rate because Europeans came to the tropics. In several generations Australians will have darker skin.
Of course, we retained the hair where it was beneficial for survival to protect large blood vessels: neck, armpits, groin, and possibly to produce pheramons during fertile period and for sexual arousal.
Discovery of fire played huge role in our history because it in significant degree protected humans from the regulation by mother nature. If any other species multiply too much, then ecological self-regulation with feed-back kicks in, resulting in growth of enemies of that species: germs, viruses, parasites. Sterilization of the food on the fire prevented many epidemics that would decimate humans otherwise. That's why majority of us like the thermically processed foods better than the raw ones. Other mechanism of self-regulating the population overgrowth is increased agression and violence which has 2 results: the over-populated species whether kill each other or run away, populating new areas. This mechanism still works alright. Suicide tendency plays insignificant in humans, unlike lemmings and "progressive" liberalism.
Another important period was 195,000 y.a. Our ancestors evolved after the Neandertal men, about 270,000 y.a., and due to the climate change (possible after huge Indonesian volcuno eruption) had to migrate to the shores. During that period selection pressure produced several features: 1) We are the only apes that can hold breath and dive; 2) we are the only apes that are born