Last Universal Ancestor/Common Descent of ALL species.
Very good Contender! This is going to be a good one I can tell. I will begin this
round with my counter-arguments. Molecular Evidence: "This area includes our common
DNA and protein functional redundancy where many basic structures are shared and support the most basic functions of life." If these areas are supporting the basic functions of life, it only makes sense that all species alive would have common DNA.
I admit this creates a plausible argument for common descent when variances go as
low as 1.2% when talking about chimpanzees, but you are talking about a it is still
a logical gap that you are trying to bridge with your conclusion that we must have
the same ancestors. We have a 1.2% difference, but you are talking about something
absurd like 300 billion lines of "coding", so 1.2% is a lot. Not to mention that scientists
don't really understand 98% of our DNA anyways (which you have already led me into).
"We can also trace "fossilized" DNA no longer useful and junk DNA strands to link
different species..." Fascinating stuff DNA. is! I am glad you brought this up, because
I had recently been reading up on this particular topic. Turns out that junk 98% isn't
really junk, and actually affects how the other 2% acts. http://www.medicalnewstoday.com...
"...and to demonstrate where different forms of life branched off from their ancestors
and all future species in the line share these characteristics." This is kind-of like
playing connect the dots with an unfathomable amount of dots, but in this case the
dots are something much more complex that we do not fully understand. http://www.nbcnews.com...
Notice how these guys always talk: "...genetic variants that seem to overlap" "We
think this is..." "This finding could suggest..." They are still figuring it out.
They are far from writing the book. Historical Phylogenetic Tree: "These start with
bacteria and eukaryotes and end with all modern forms of life. Here common decent
was largely established based on observable characteristics of species often in the
geological fossil records." All of the fossils show variances within a species, not
species becoming other species in any way shape or form. They explain the tree as
connecting all species, but when you look at the fossils, they have something that
looked kind-of like an octopus and say "aha! Must be the ancestor of the octopus (instead
of perhaps a deformed or runt octopus). Ok, well maybe it is, but at some point you
have to take all our ancestors and explain how they all evolved separately from bacteria.
Furthermore, the bacteria is only ever seen mutating into bacteria; viruses into viruses.
We have no fossilized bacterias from the earliest stages in the so called "tree of
life", so it is pure speculation to begin with. "There are many examples of animals
with anatomical vestiges from the past such as whales with hind limbs." There is also
a despised fish called a "snakehead" which eats everything in a river and then grow
leg-like fins which allow them to travel for up to four days. Whether forwards or
in reverse, its a variation within species, not a transition to another species. The
snakeheads do not become mammals. We could assume that much older cases are legitimate
transitions, but how would a whale walk about on land? Whales don't come right before
bipedal animals in the evolutionary tree, so what kind of weird stuff is going on
here? "There is also a lot of embryological evidence where different developing structures
form different features depending on the species." I am interested to see you expand upon this point, as this is something I have never
heard before and do not fully understand what you mean yet. Speciation. This is also
one of those arguments that sounds good at face value, but the conclusion does not
necessarily result from the premises (a fish can adapt to become different but very
similar fish, therefore a fish can also become a mammal). Now might be a good time
to mention that I do accept adaptation and natural selection, if that helps you with
my perspective a little bit. I am not saying that species stopped adapting, I am saying
species adapt to their environment and not into other species. If that were the case,
we would still have transitionals all over the place. Where are the whale-mammals?
A whale fossil that appears to have hind legs (which might very well be something
els hybrid does not impress; I have already conceded common ancestry from species
to species. "(Opportunism and evolutionary restraint) reveal that new structures form
from old structures making rapid changes difficult and certain changes nearly impossible."
Opportunism is a theory that explains away the non-variances that remain after a "transition".
This is comparable to saying "dogs still have tails, but they're for wagging now instead
of swatting flies". In biology, it is simply a description of one organisms capability
to adapt to different environments. Strong evidence for adaptation, not special transition.
Evolutionary restraint poses issues for common descent in some circumstances. Sterile
hybrids leave the question of how transitional organisms are able to stick around
long enough to evolve into anything else, or why such a useless trait would even evolve
to begin with. Also, if nature is "selecting things", then adaptation may not be its
only option. Restraint doesn't lend anything to the idea that species become other
species. ________________________________________________________________________________________________________________
How many years? First let me say, I am not a fundamentalist. 10,000 years is a ridiculous
idea as well as 4.5 billion. It is not simply a fear of big numbers, but a number
of factors which go into my problems with the accepted timeline: Dating Methods- I
have already explained my overarching point here, so now I will expand upon this idea.
We know that c14 dating fails around 15,000 years, while other radiometric dating
methods are assumed to be accurate beyond this because we can't know otherwise. This
again reflects a general desire within the scientific community to conduct research
within a Darwinian envelope. Matter is neither created nor destroyed; it only changes
forms. Therefore, no new matter is entering the universe. These isotopes, again, should be long gone, and the half-life is more of a speculation than a certainty. There
are other problems as well-- for instance, in many published cases, radiometric dating
of rocks or fossils did not line up with the geological or evolutionary timelines.
In other cases, different samples were taken of the same fossil, and produced drastically
different guesses. We also have no way of knowing whether the decay from isotope to
half-life to decay rate remains constant, since we can't do experiments that are millions
of years long. Moon Landing-- Apollo 11 found an average of a half inch of space dust
on the moons surface. If it had been there for as long as they say, their should be about 54 feet, being that the moon has no atmosphere. Skewed geological record.
Scientists now accept the global flood which is related in many ancient cultures,
or some variation on it, but place it millions of years back. This completely ignores
the effect it would have had on our geological record, especially if such an event
broke up Pangea. It also doesn't explain why there are written accounts of what probably
was a surviving oral tradition passed down by survivors. There would have been mass
and in some cases instantaneous fossilizations, even more so if a super-volcanic eruption
preceded the event (which has been suggested). Lack of evidence for civilizations
predating 20,000 years ago (at maximum estimate). There is simply no reason to believe
that other creatures predate man, if you do not accept the dating methods which place
them further back. Early stories such as Job feature the Leviathan and Behemoth, while
other cultures spoke of the Hydra and Dragons. This makes it hard to believe that
early man did not encounter dinosaurs before they went extinct. I don't think you're
description of Irreducible complexity is accurate. The idea behind it is that most
organisms are comprised of complex systems-- each comprised of their own characteristics,
and interdependent upon one another. For instance, there are many different types
of eyes that creatures may have, such as Spherical or Refractive. Each is comprised
of several parts, all of which are required for the eye to work. This can't evolve,
unless you are evolving several different working components simultaneously, like
a clock built in one step. "If it could be demonstrated that any complex organ existed
which could not possibly have been formed by numerous, successive, slight modifications,
my theory would absolutely break down." --Charles Darwin My point on the uniqueness
of man is that there should be other species with the same capabilities, and this should be evident if we have been here 4.5 billion years. Also, humanity is inherently self-destructive--
the only species with both instinct and the free will to defy it against our own best
interests. We most certainly are not products of natural selection, if you think about
it, or we wouldn't be building nuclear weapons. "Humans are still monkeys" -- This
is a hard argument to understand. I will "The majority, if not all, monkeys like ourselves
have changed dramatically from our ancestors ~ 6 million years ago." - This is an
assumption. Why are there still monkeys? Didn't they all evolve to the point there
were no more transitionals left? How are there monkeys left? "I think this is fairly
accurate and evolution phylogenetic tree looks like a bush with many evolving pathways
leading to dead ends and roughly 99%+ species that have existed are estimated to be
extinct." It is a cool l
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