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QUOTE FOR THE DAY

Explore the fascinating journey of human evolution and the origins of our African ancestors. Discover the scientific theories and evidence that trace our lineage back millions of years.

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QUOTE FOR THE DAY

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  1. QUOTE FOR THE DAY Human beings, who are almost unique in having the ability to learn from the experience of others, are also remarkable for their apparent disinclination to do so. Douglas Adams There is a theory which states that if ever anyone discovers exactly what the Universe is for and why it is here, it will instantly disappear and be replaced by something even more bizarre and inexplicable.There is another theory which states that this has already happened. Douglas Adams

  2. RELATIVES

  3. HUMAN EVOLUTION OR ARE WE THERE YET?

  4. SCIENCE HAS NOT BEEN USED WITH OPEN MINDEDNESS IN ALL CASES IN THE STUDY OF HUMAN EVOLUTION AND RACE. “Wherever people use physical appearance to judge the character of others, the mindlessness of bigotry is close at hand. People are no longer individuals with unique attributes; they’re seen only as representatives of types.” - Steve Olson -

  5. AFRICAN APES HAVE EXISTED FOR SEVERAL MILLION YEARS (~23 MILLION). AROUND 6 MILLION YEARS AGO, A POPULATION SPLIT INTO TWO GROUPS - ONE WOULD LEAD TO HUMANS, MODERN CHIMPANZEES, AND GORILLAS AND THE OTHER TO OLD WORLD MONKEES. AROUND 4 MILLION YEARS AGO, ONE SPECIES ON THE PATH TO HUMANS WAS ABLE TO SPEND MOST OF ITS TIME ON TWO FEET. THIS SPECIES COULD USE ITS HANDS IN NEW WAYS AND DEVELOPED A LARGER BRAIN. THESE ARE PLACED IN THE GENUS AUSTRALOPITHECUS.

  6. ABOUT 2 MILLION YEARS AGO, A SPECIES WITH A LARGER BRAIN STILL WAS ABLE TO MAKE RUDIMENTARY TOOLS FROM STONES. THIS SPECIES WAS THE FIRST TO EARN THE GENUS HOMO. ALL OF THE EVENTS DESCRIBED TOOK PLACE IN AFRICA WITHIN 500 MILES OF THE EQUATOR. SCIENTIST THINK THAT 1.8 MILLION YEARS AGO, AS MANY AS 4 DISTINCT GROUPS OF HUMANS AND AUSTRALOPITHS SHARED THE SAME HOMELAND IN EAST AFRICA.

  7. FINALLY, BETWEEN 100,000 AND 200,000 YEARS AGO A NEW GROUP APPEARED WITHIN THE GENUS HOMO. THIS GROUP WAS LESS HEAVILY BUILT, MORE MOBILE, AND HAD BETTER COGNITIVE SKILLS. IT IS DIFFICULT TO DRAW A STRAIGHT LINE FAMILY TREE, AS FOSSIL EVIDENCE JUST DOESN’T EXIST. THE OLDEST KNOW FOSSIL SKULL BELONGING TO THIS GROUP WAS DISCOVERED BY RICHARD LEAKEY IN 1967 ON THE OMO RIVER IN ETHIOPIA. THIS WAS DATED AT ABOUT 130,000 YEAR AGO.

  8. SCIENTISTS HAVE NEW WAYS OF TRACKING EVOLUTION - DNA - IN PARTICULAR MITOCHONDRIAL DNA AND Y CHROMOSOME DNA. MITOCHONDRIAL DNA IS TRANSMITTED BY FEMALES. Y CHROMOSOME DNA IS TRANSMITTED BY MALES. THEY BOTH TELL SIMILAR STORIES. EACH GENERATION ADDS VARIATION TO DNA. THE AMOUNT OF VARIATION MEASURES HOW MANY GENERATIONS HAVE PASSED SINCE COALESENCE.

  9. COALESCENCE IS WHERE DNA IN A NUMBER OF PEOPLE CAN BE TRACED BACK TO A SINGLE PERSON. IN THE CASE OF MITOCHONDRIAL DNA AND Y CHROMOSOME DNA, COALESCENCE OCCURS AROUND 150,000 YEARS AGO. ALL OF OUR MITOCHONDRIAL DNA CAN BE TRACED BACK TO A SINGLE FEMALE WHO LIVED AROUND 150,000 YEARS AGO.

  10. ALL OF OUR Y CHROMOSOME DNA CAN BE TRACED BACK TO A SINGLE MALE WHO LIVED ABOUT THIS SAME TIME. THERE ARE ANCIENT GROUPS OF PEOPLE STILL LIVING IN AFRICA WHO ARE RELATED TO OUR AFRICAN ANCESTORS - PEOPLE WHO REMAINED IN AFRICA. ONE NOTABLE GROUP IS THE SAN BUSHMEN WHO LIVE ON THE EDGE OF THE KALAHARI DESERT IN NAMIBIA AND BOTSWANA.

  11. PEOPLE TALK ABOUT WHO THEY ARE DESCENDED FROM. AS MUCH INTERMIXING AS HAS OCCURRED, WE DON’T HAVE TO GO BACK TO FAR TO SEE THAT WE ARE RELATED TO EVERYONE. IF WE ASSUME A GENERATION IS 20 YEARS. EACH GENERATION HAS TWO PARENTS. IF YOU GO BACK TWO GENERATIONS, YOU HAVE FOUR GRANDPARENTS. THREE GENERATIONS, AND YOU HAVE EIGHT GREAT GRANDPARENTS. TEN GENERATIONS, AND EACH OF US HAD 1,024 GREAT-GREAT-GREAT-GREAT-GREAT-GREAT-GREAT-GREAT GRANDPARENTS.

  12. 30 GENERATIONS WOULD TAKE US BACK TO 1400, AND EACH OF US WOULD HAVE 1,024 X 1,024 X 1,024 ANCESTORS. THAT IS MORE THAN A BILLION, AND ONLY 375 MILLION PEOPLE EXISTED AT THAT TIME. SOME WHERE IN THERE, COUSINS HAD TO MARRY. IF YOU THINK YOU WERE RELATED TO SOMEONE FAMOUS IN THE 15TH CENTURY, YOU PROBABLY WERE. AN ASIDE - OFTEN OUR ANCESTORS ARE NOT WHO WE THINK THEY WERE.

  13. NOW, LET’S GET BACK TO OUR AFRICAN ANCESTORS. PEOPLE LEFT AFRICA AT VARIOUS TIMES IN THE PAST. ICE AGES TIED UP LOTS OF WATER, AND THIS USUALLLY RESULTED IN DRIER CLIMATES. IN AFRICA, MUCH OF WHAT WOULD HAVE BEEN LUSH TROPICAL FORESTS WOULD HAVE BECOME GRASSLAND AND SAVANAH. WHAT WAS GRASSLAND MIGHT HAVE BECOME DESERT.

  14. SOME OF THE ARCHAIC HUMANS LEFT AFRICA AS EARLY AS 500,000 YEARS AGO OR EARLIER. SOME OF THESE DID NOT SURVIVE, BUT ONE GROUP, THE NEANDERTHALS SURVIVED UNTIL ABOUT 30,000 YEARS AGO. OF THE MODERN HUMANS, ONE GROUP LEFT ABOUT 100,000 YEARS AGO AND SETTLED IN THE MIDDLE EAST. THIS GROUP DID NOT SURVIVE, BUT LEFT ARCHEOLOGICAL EVIDENCE. ANOTHER GROUP LEFT BETWEEN 60,000 AND 50,000 YEARS AGO AND TRAVELED ALL THE WAY TO AUSTRALIA.

  15. THE AUSTRALIAN ABORIGINES HAVE ONE OF THE LONGEST CONTINUAL CULTURES IN EXISTENCE. MODERN HUMANS REAPPEARED IN THE MIDDLE EAST ABOUT 40,000 YEARS AGO. AT ABOUT THE SAME TIME, NEANDERTHALS IN THIS AREA DISAPPEARED. IT HAS BEEN HOTLY DEBATED WHETHER MODERN HUMANS AND NEANDERTHALS EVER INTERBRED. THERE IS NOW SOME GENETIC INDICATION THAT THEY DID. KNOWING THE PROPENSITY OF THE HUMAN RACE TO COUPLE WITH ALMOST ANYTHING, THERE SHOULD BE LITTLE DOUBT.

  16. THE HUMANS THAT LEFT AFRICA FROM ABOUT 65,000 YEARS AGO ON, WERE MUCH DIFFERENT FROM THOSE THAT LEFT EARLIER. THEIR TOOLS AND CULTURE WERE MUCH MORE SOPHISTICATED. THIS WAS PROBABLY DUE TO THE APPEARANCE OF LANGUAGE. ABOUT 40,000 YEARS AGO, MODERN HUMANS WERE LIVING IN MALAYSIA, THAILAND, VIETNAM, AND THE PHILIPPINES. AS EARLY AS 26,000 YEARS AGO, HUMANS WERE LIVING AS FAR NORTH AS BEIJING.

  17. OTHER GROUPS MOVED ACROSS THE NORTH OF ASIA TO SIBERIA. ALSO, ABOUT 40,000 YEARS AGO, MODERN HUMANS SETTLED IN EUROPE. HOWEVER, THEY ABANDONED NORTHEN EUROPE DURING THE LAST ICE AGE, AROUND 20,000 YEARS AGO. HUMANS CAME TO THE AMERICAS LAST. AROUND 16,000 YEARS AGO, WALKING ACROSS CANADA TO WHAT IS NOW THE U.S. WAS IMPOSSIBLE. THEN, ABOUT 14,000 YEARS AGO, A CORRIDOR OPENED IN THE ICE.

  18. THE OLDEST FOSSIL EVIDENCE OF HUMANS IN NORTH AMERICA IS THAT OF KENNEWICK MAN. THESE BONES HAVE BEEN DATED TO ABOUT 13,500 YEARS AGO. THE BONES WERE DISCOVERED ALONG THE COLUMBIA RIVER. SEVERAL SITES HAVE BEEN DATED EARLLIER THAN THIS. AT LEAST THREE WAVES OF PEOPLE SETTLED THE AMERICAS. THE EARLIEST GROUP IS REPRESENTED BY THE MAJORITY OF THE AMERIND GROUPS.

  19. THE NEXT GROUP IS REPRESENTED BY THE NORTHWEST TRIBES AND THE NAVAJO AND APACHE. THE LAST GROUP IS REPRESENTED BY THE ESKIMO-ALEUT TRIBES. IT IS IMPORTANT TO REMEMBER THAT THINGS THAT WE ASSUME AS “RACIAL” CHARACTERISTICS CAN BE CHANGED IN VERY SHORT PERIODS OF TIME - AS LITTLE AS 10,000 YEARS. SKIN COLOR IS A GOOD EXAMPLE OF THIS. REMEMBER, TOO THAT WE SHARE MORE THAN 98% OF OUR GENETIC MATERIAL WITH GORILLAS AND CHIMPANZEES.

  20. IF PLANETARY UPHEVAL WERE AN OLYMPIC SPORT, HUMANS WOULD WIN THE GOLD. MANY SCIENTISTS NOW BELIEVE THAT HUMANS ARE DRIVING EVOLUTION OF SOME SPECIES AT A RAPID RATE. ANTIBIOTIC RESISTANT BACTERIA - O157:H7 E. COLI, METHICILLIN-RESISTANT Staphylococcus aureus, TB, HIV PESTICIDE RESISTANT INSECT PESTS GMO’S AS FOOD SOURCES REFERENCE: Stephen R. Palumbi, The Evolution Explosion

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