I am so bored in school today so i read up on scientific stuff. It is what i always do when i am bored. So this time round I read up on fertilisation and human evolutions.
SO this is what I have read up on.
I didnt really start reading on fertilisations at first...but it came only after i was reading on the news about the water flows backwards in the Amazon River. Second longest river in the world...The first longest river is the Nile River in Egypt.
"After a male has successfully inseminated a female, there's still a long way to go before fertilization can take place. That's because the female bodies of many species are not passive arenas within which sperm compete, but more like obstacle courses, with hurdles and defenses in place to weed out weakling sperm.
For example, the female reproductive tract might release harsh chemicals harmful to sperm, or it might evolve to become intentionally long so that the race to fertilization becomes a test of sperm endurance.
Males ejaculate hundreds of millions of sperm into the female reproductive tract, but most don’t make it to the egg for fertilization. In mammals, just .001 percent of the ejaculated sperm hit the fertilization target.
We know that the reproductive tract in females can be a nasty place for sperm but the acidity can kill many sperm, and scientists think some females’ immune systems attack sperm as a “foreign object.”
The seminal fluid in a male’s ejaculate helps to buffer the acidity, creating more viable conditions for sperm. By waiting in line, males could exploit the ejaculate from other males, giving their sperm a cushy ride into the female’s uterus to fertilize eggs.
As for animals, Studies have shown that the the last male to mate with a female is the most successful at impregnating her.
Going last means that the male could lower the amount of sperm in his ejaculate since there’s a higher probability of that sperm being successful. Producing sperm is a costly investment and has been shown to require a good chunk of an animal’s resting energy. "
Adapted from livescience.com
I just cut and paste certain parts out and put it together.
Long time ago long before sex took place, organisms produced through asexual reproduction. cool Right...
But somehow it brought about sex...
Wah...that is how mutation started in organisms. Initially production through asexual reproduction is more of cloning then mutation.
Hmmm...that's all...Certain parts i just copied and paste it in.
Argh...so many things take place...haha...so find out more if u wanna know more...
It's tiring for me to go to the bottom and read up on it.
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Soldier 
