Human evolution – some thoughts
I cannot tell you how many times it’s happened that, upon learning that I’m a
scientist, people have said to me: ‘So, you believe in evolution? Does that mean that you
believe we came from monkeys / chimpanzees / gorillas …?’ or ‘So, you believe in
evolution, tell me what will we become?’ In a way, these questions frustrate me, but in
fact, they reflect an appalling lack of scientific education in the schools, and a terribly
worrisome lack of political will to stand up against the aggressive, and self-satisfied
ignorance of the ignorant masses in certain countries (though perhaps I am being unfair
on the politicians here, perhaps they too actually are as ignorant and unschooled as the
bulk of the citizenry they represent – I would refer the doubter of this proposition of
mine to Hank Johnson’s concern that the island of Guam might tip over and sink. Watch
it here: http://www.youtube.com/watch?v=zNZczIgVXjg).
Source: http://www.dailymail.co.uk/sciencetech/article-1070671/Evolution-stops-FutureMan-look-says-scientist.html
N. B. that the ape like animal to the extreme left is not a modern ape, but an early, now
extinct ape-human ancestor.
I’m not sure what it is exactly, but evolution and the big-bang theory more than
most other ideas in science are the ones which seem to bring out the most primitive
knee-jerk reactions in people. It ought not be too surprising though I suppose, since they
both deal with origins, and most of the canonical religions with their dogmatic
ontological and eschatological doctrines cannot fundamentally reconcile their belief
system with the basic tenants of evolutionary theory, as these religions all explicitly
posit a definite and special act of creation, but that shall be the subject of another post.
Today, I would like to confine myself to addressing the two questions I noted at the
beginning of this post.
To answer the second question first, we do not know what we will evolve into.
Unless one believes, however mistakenly, in some sort of pre-destination, one has no
idea of how the chaotic process of evolution (and I use the term chaotic in its strictly
scientific sense) will proceed. I of course would add the caveat that even if one were to
believe in pre-destiny, that would not mean that one actually had any clue, only that one
had simply deluded oneself into thinking that one did.
In fact, we may not evolve any further at all. There are some geneticists who
argue that human evolution has ground to a halt, and that we shall not change much
physiologically from the form we now have because the forces driving evolution – viz.,
natural selection and genetic mutation – no longer play an important role for us. (Read
more about this at: http://www.dailymail.co.uk/sciencetech/article1070671/Evolution-stops-Future-Man-look-says-scientist.html#ixzz1ruHZCGAv)
Source: http://www.pbs.org/wgbh/nova/id/pred-09.html
Fearing that many of his contemporaries would be deeply offended if he suggested that humans and apes
share a common ancestor, Darwin barely touched on human evolution in the 1859 Origin of Species. But by
the 1871 Descent of Man, he was ready, stating baldly that "man is descended from a hairy, tailed
quadruped, probably arboreal in its habits." He also maintained that the difference between the mind of
man and that of a chimpanzee or gorilla is a matter of degree, not of kind. Summing up, Darwin wrote, "We
must … acknowledge, as it seems to me, that man with all his noble qualities … still bears in his bodily
frame the indelible stamp of his lowly origin." Today, many a schoolchild can cite the figure perhaps most
often called forth in support of this view—namely, that we share almost 99 percent of our DNA with our
closest living relative, the chimpanzee. (The illustration shown here appeared in T. H. Huxley's 1863 book
Man's Place in Nature. All skeletons are to scale except the gibbon, which is shown twice natural size. )
Anyway, getting back to evolution, even if the process has not ground to a halt for
our species, no one knows how long it will be before our species evolves into some other
form, though given how we are exploiting the planet and its limited resources, this may
be a moot point, as we may all be extinct before any significant evolution of our species
can take place. Actually, let me go back and rephrase that. In a sense, we are evolving all
the time: the fact that some ethnic groups are more resistant to malaria than others; or
the fact that as a result of modern medicine, there are proportionately far more people
with weaker resistance to diseases than there were 500 years ago; or that there are
proportionately more people with poor eyesight than there were 10,000 years ago; or
that blue-eyes and the AB blood type likely appeared relatively late in our history all
constitute evidence of evolution amongst our species (something I shall cover in a future
post).
Source: http://therelativelyinterestingblog.blogspot.com/2010/01/if-humans-evolvedfrom-apes-why-do-apes.html
All the animals at the top are from the same or close to the same ‘generation’ if you
like; i.e. are cousins (strictly speaking, this is not exactly true, since different species have
different life-expectancies, and become capable of breeding (reach sexual maturity) at
different ages, so whereas humans can essentially start breeding after about a dozen years
of life, baboons can so do after only half that time, so if you and a baboon were both to be
born on the same date, it would likely become a grandparent well before you were even a
parent).
Source: http://sciencerevolution.net/evotree.html
The above diagram gives some idea of when the various species indicated branched out
from each other, and of roughly how far apart – genetically speaking – they are from each
other.
As to us coming from monkeys and apes, the situation is a little more complex
than this, but not really all that much: to put this in basic terms, as you can see from the
two diagrams above, all currently living apes and more distantly currently living
monkeys (and progressively more distantly other currently living life-forms) are our
‘cousins’, not our ‘uncles’ or ancestors.
Furthermore, you (regardless of who you are) and I (regardless of who I am), at
some point in our history, do share a common ancestor; you and the chimpanzee you
watched on TV the other night also share a common (non-human) ancestor, albeit
(hopefully) somewhat further back in time; you, your cousin the chimp, and any monkey
you care to name also share a common (non-ape) ancestor, even further back; and you
and any other life-form either currently living or now extinct at some point do share a
common ancestor: so yes, in a very remote way, even the dinosaurs were in some way
related to you, albeit not directly (i.e. they were in no sense your ancestor), and myriads
of times removed. Even better, one of your (pre-pre-pre-…human) ancestors actually
was a ‘cousin’ to a dinosaur, in the same way that you are related to both apes and,
vastly more remotely, to cucumbers.
I would now like to address another related question here, which I have also
sometimes been asked: If humans evolved from apes, why do apes still exist? Well, the
answer is that humans did not evolve from apes, and humans and apes did not evolve
from monkeys, rather, humans and apes evolved from some common human-ape
ancestor and the two branches took different evolutionary paths, in the same way that
the human-ape ancestor’s distant ancestor diverged at some point from the common
ancestor it shared with the monkey-ancestor. The parallel is with Africans, and AfricanAmericans, or White Americans and White Europeans: when Africans were brought to,
or White Europeans came to America, that did not bring human existence in Europe or
Africa to a screeching halt, not all the humans on those two continents moved (just as
not all the offspring of the ape-human ancestor became humans), and so, Africans and
Europeans continued to live and breed in their home continents, and the migrants began
to live and breed in America. Any given Afro-American or Euro-American however is
clearly related to people in his/her home continent. It’s just a matter of going back far
enough in time to find that point.
Source: http://www.musicstack.com/album/herbie+mann/early+mann
Herbie Mann certainly got it right (more or less).