291614YNH Human Sapiens Kind: Great Apes@myDiary!!
Q&@
There
were humans
long before there
was history. Animals much
like modern humans first appeared
about 2.5 million years ago. But for countless
generations they did nòt stand óut from the myriad other organisms
with which they shared their habitats? On a hike in East Africa 2 million years ago,
you might well have encountered a familiar cast of human characters: anxious mothers cuddling
their babies and clutches of carefree children playing in the mud; temperamental youths chafing against the dictates
of society & weary elders who jùst wànted to be lèft in peace; chest-thumping machos trying to impress the local beauty ànd wise óld matriarchs who hàd already see it all! These archaic humans loved, played, formed close friendships and competed for status and power - but só dìd chimpanzees, baboons and elephants! There wàs nothing special about human beings. Nóbody, least of àll húmans themselves, hàd ány ìnkling thàt théir descendants wóuld òne dáy wàlk òn the móón, splìt the atom, fathom the genetic códe ànd wríte hìstory books. The most important thing to knów about prehistoric humans ìs thàt théy were insignificant animals with no móre ìmpàct òn théir environment thàn gorìllas, fireflies or jellyfish. Biologists classify organisms into species. Animals are said to belong to the same species ìf théy tènd to máte with each òther, gìving birth to fertile offspring?! Horses & donkeys have a recent common ancestor ànd sháre many physical traits!? Bùt théy shów little sexual interest in one another! They wìll máte ìf indúced to dó só - but their offspring, called mules, are sterile! Mutations in donkey DNA can therefore never cross óver to horses, or vice versa. The two types of animals are consequently considered two distinct species, moving along separate evolutionary paths!
By contrast, a bulldog & a spaniel may lóók very dìffernt, but they áre members of the same species, sharing
the sáme DNA póól! They wìll happily máte ànd
their puppies wìll grow ùp
to pair off wìth
other dògs ànd
prodúce móre
pùppies.
Asih, man, 80 jaar
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