Humans are still evolving

Discussion in 'Human Science' started by Plazma Inferno!, Jul 18, 2016.

  1. Plazma Inferno! Ding Ding Ding Ding Administrator

    Messages:
    4,609
    Have we stopped evolving? Whether the human race is still adapting to our surroundings is heavily debated – and now fresh genetic analyses by Harvard University’s Jonathan Beauchamp suggest we can control our surroundings, but it doesn't necessarily mean we're immune to natural selection..
    Beauchamp compared genomes and traits of 20,000 older people with the number of children they’d produced, and found natural selection favours less schooling and a higher age of first menstruation.
    He used a statistical test to analyse 20,000 Europe-descended Americans born between 1931 and 1953, part of the University of Michigan’s Health and Retirement Study. (They were chosen as their childbearing years were likely behind them.)
    In terms of evolution, the more offspring a person has, the more times their genes can be passed on and the better their “evolutionary fitness”. When compared to the average brood for the population of their age, for instance, this is known as relative lifetime reproductive success.
    He found people who had more kids – so were more evolutionarily fit – tended to have lower education levels, and the women were older at the time of their first menstruation.
    But there are a number of limitations to the work, Beauchamp admits.

    https://cosmosmagazine.com/biology/humans-are-still-evolving-study?

    Study: http://www.pnas.org/content/113/28/7774
     
  2. Google AdSense Guest Advertisement



    to hide all adverts.
  3. wellwisher Banned Banned

    Messages:
    5,160
    An interesting observation is there are more poor people in the world; blessed are the poor, than other economic groups. If we go by numbers, being poor has a connection to natural selection.

    This makes sense since being poor does not allow one use social prosthesis to compensate for genetic deficiencies. This closer to how nature evolves life. Richness allows more access to social prosthesis to compensate for genetic deficiencies. This allows social advantage through artificial selection.
     
  4. Google AdSense Guest Advertisement



    to hide all adverts.
  5. origin Trump is the best argument against a democracy. Valued Senior Member

    Messages:
    9,831
    How so?

    What is a social prosthesis?

    I am not sure what you mean, could you expound on this?
     
  6. Google AdSense Guest Advertisement



    to hide all adverts.
  7. timojin Valued Senior Member

    Messages:
    3,066
    Yes evolving: Dominican republic Have one village were 1 of 9 male are born without pinus . I Brazil there are several families whose offspring have 6 functional fingers on each hand . In Turkey there is a family were the children walk on fore limbs. Called evolve or whatever.
     
  8. origin Trump is the best argument against a democracy. Valued Senior Member

    Messages:
    9,831
    I would call these birth defects. What is a pinus? Do you mean penis?
     
  9. DaveC426913 Valued Senior Member

    Messages:
    6,652
    There are always variations in every species.
    The human race would only evolve to have six fingers if it became ubitquious in an isolated population.
     
  10. DaveC426913 Valued Senior Member

    Messages:
    6,652
    I was kept alive because of welfare. Well... employment inusrance - which allowed me to keep my home, and thus have children, evne when I didn't have work. Not necessarily something they have in third world countires.
    I was kept alive because of an inhaler, which I had access to because I live in a First world country that provides such things.
    We have all sorts of accessibility laws that enable the disabled to live normal, productive (reproductive) lives.

    So, I am able to pass along my faulty genes better than someone who did not have access to such societal supports.

    Yes, which we can correct or compensate for, leading to more likelihood of offspring.

    I believe that is what he is saying.
     
  11. timojin Valued Senior Member

    Messages:
    3,066
    Dick. Why defect they have I believe two or three generation born with out a dick and no testicles but the testicles or dick grow after puberty
    Dick
    I believe the village in the Dominican republic there are already in the third generation , and the Brazilian family in the second generation/ You want to call it error, good for you. By the way the boys which are born without a dick but with testicles and at the puberty age the dick started to grow. How about that for evolution.
     
  12. spidergoat Valued Senior Member

    Messages:
    51,741
    Those boys have an inherited genetic condition, a lack of an enzyme that converts testosterone into another form. So this is a genetic variation, which, if beneficial, could become more widespread. Is it evolution? Technically, it's a change in allele frequency, so yes.
     
  13. sculptor Valued Senior Member

    Messages:
    4,436
    evolve or go extinct
    whither hence?
     
  14. Bells Staff Member

    Messages:
    22,062
    What are you talking about?

    Do you mean the Guevedoces from the Dominican Republic?

    One of the first people to study this unusual condition was Dr Julianne Imperato, a Cornell endocrinologist. She travelled to this remote part of the Dominican Republic in the 1970s because of strange rumours about girls turning into boys

    She eventually unraveled the mystery of what is going on and by doing so helped make a surprising medical breakthrough.

    At conception we all inherit a set of genes from our parents that will, in time instruct our bodies to make us male or female. But for the first few weeks of our lives human embryos are neither. Instead we have a protrusion called a tubercle. If you’re genetically male the Y chromosome instructs the gonads to become testicles. They also send testosterone to the tubercle, where it is converted into a potent hormone called dihydro-testosterone This transforms the tubercle into a penis. If you’re female and don’t make dihydro-testosterone then your tubercle becomes a clitoris.

    When Dr Imperato investigated the Guavadoces she discovered the reason they don’t have male genitalia at birth is because they are deficient in an enzyme called 5-α-reductase, which normally converts testosterone into dihydro-testosterone. So they appear female when they are born, but around puberty, when they get another surge of testosterone, they sprout muscles, testes and a penis.

    It is an inherited genetic condition, and it exists in pockets of South America, as well as in Papua New Guinea.

    Is it beneficial? I don't think so, since they tend to have smaller testes and genitals, as well as smaller prostates. They do go on to live normal lives, however. Time will tell.
     
  15. timojin Valued Senior Member

    Messages:
    3,066
    One of the boys in Brazil of the families with six fingers on each hand he was actually proud, he said it was great for goalkeeper in soccer because his hands were larger. So here you are a benefit of mutation for soccer games/
     
  16. Bells Staff Member

    Messages:
    22,062
    Because soccer is beneficial in an evolutionary sense?

    Babies are born with birth defects, such as extra digits or even extra limbs. This occurs often in poverty stricken countries where access to clean water and proper nutrition, not to mention an over-exposure to chemicals and pollutants, can cause such defects.

    Well, more to the point, it occurs more in third world or developing countries than in developed nations.

    Birth defects can also be genetic. But one should not ignore the environmental causes.

    http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2897222/

    http://www.who.int/ceh/publications/factsheets/fs284/en/

    If you wish to look beyond birth defects as signs of evolution, you should focus on how we are now lactose tolerant in many parts of the world, you should look at our wisdom teeth, the fact that human brains have been getting smaller because it is more efficient, women's pelvis size and it's change over the last few thousand years. Blue eyes and blonde hair, is another sign that evolution is still an ongoing process.

    http://www.sciencemag.org/news/2016/05/humans-are-still-evolving-and-we-can-watch-it-happen

    http://mentalfloss.com/article/30795/5-signs-humans-are-still-evolving
     
  17. timojin Valued Senior Member

    Messages:
    3,066
     
  18. spidergoat Valued Senior Member

    Messages:
    51,741
    Genetic mutations that become more common in the gene pool and examples of evolutionary changes. We also call them birth defects. You seem to assume that negative changes can't be evolution.
     
  19. timojin Valued Senior Member

    Messages:
    3,066
    Would you call it devolution ?
     
  20. spidergoat Valued Senior Member

    Messages:
    51,741
    No.
     
  21. Fraggle Rocker Staff Member

    Messages:
    24,690
    Every definition of "evolution" that I've ever seen encompasses, in one way or another, the insistence that the thing which is evolving will be improved by the specific evolutionary change. Or... at the very least, that it will not cause the thing to become less suitable for its environment and risk becoming extinct.

    So yes: Negative change cannot be evolution.
     
  22. origin Trump is the best argument against a democracy. Valued Senior Member

    Messages:
    9,831
    Devolution would be survival of the least fit to survive. Since the most able to survive do in fact survive, devolution makes no sense.

    For instance if 5,000,000 years from now mankind has changed to a simian creature living in trees as family groups with no ability for language, that would still be an example of evolution.
     
  23. Fraggle Rocker Staff Member

    Messages:
    24,690
    Amusingly enough, two of our closest relatives, the chimpanzee and the gorilla, have learned to communicate in American Sign Language. (Yes, there are two species of chimpanzee and two species of gorilla. I have never found an article that gave their taxonomy.)
     

Share This Page