Before we even begin this video a simple but necessary clarification must be made; people
very often confuse abiogenesis with evolution, and they shouldn’t.
Abiogenesis is the study of how life first emerged from non-living matter, and it’s
not discussed within this video.
Evolution, on the other hand, is the study of “biological change over time”, and
it is the star of this video.
Now with that said and out of the way, let’s get on with the video.
The evidence for evolution comes from every branch of science that remotely interacts
with organisms.
This includes, to name but a few, anatomy, biology, embryology, genetics, neurobiology,
and paleontology – which in turn includes every sub-field of these sciences, such as
anthropology, biogeography, chronological dating, comparative anatomy, fossils, molecular
biology, and the list goes on and on and on and on…
The point being here is that everything we objectively know about the natural world both
supports and improves the theory of evolution by natural selection, whether we like it or
not!
This, is 9 Proofs of Evolution – Why Evolution is True.
Now to present all of the evidence for evolution would take eons, and would bore even Darwin,
Dawkins and Jay Gould, and so if you’re really interested in reviewing all of the
overwhelming evidence for evolution, then this video isn’t it… what it is, however,
is just nine lines of evidence from several fields of study which by themselves alone
make a very convincing case.
So, where to begin?
Well, the first two lines of evidence that I’m going to present both come from the
comparative anatomy of whales to land mammals.
We’ve long known that despite whales looking like fish, they’re mammals, because just
like mammals, and unlike fish, they give birth to live young; feed their young milk via their
mammary glands; breathe through two lungs rather than gills; have skin and hair rather
than skin and scales; and they’re warm blooded.
Now this alone strongly implies that they share a common ancestor with land mammals,
but what really makes this suggestion even more compelling, and what I’ll offer as
a first line of evidence, is the curious bone structure of their flippers…
Within their flippers, whales have, just like the forelimbs of land mammals, finger, hand,
wrist, and arm bones, which can be easily explained if these bones are repurposed forelimbs,
but are remarkably hard to explain if they’re not, as after all, these bones have very little
in common with non-mammal fins, and yet a great deal in common with the forelimbs of
land mammals.
Furthermore, and to invoke a second line of evidence, whales have strange bones that look
like shrivelled hip, thigh and shin bones where land mammals have hind legs, and some
of these bones, such as these from a bowhead whale, even have what appears to be a ball
and socket joint… further still, palaeontologists have found numerous species within the fossil
record that have unique similarities with whales, but also varying sizes of hind legs.
Now once again, these bones make perfect sense if they’re vestigial and / or repurposed,
but they’re very peculiar if they’re not.
Talking of vestigial traits, and to present a third line of evidence, a superb example
of one can be found in all mammals (including you), and it’s called the left recurrent
lar-yn-geal nerve.
Without getting to technical, this nerve runs from the brain to the voice box, which should
be a distance of a few inches, but instead it goes down into the chest, loops around
a main artery, and then goes back up to the voice box, which in the case of the giraffe
results in a 15 foot detour…
“A mistake that no engineer would ever make!”
However, in animals without a neck, such as fish, the most direct route for this nerve
is indeed by navigating round the artery, and hence, if mammals evolved from fish-like
ancestors, we can easily explain why this absurd design exists.
But if, on the other hand, we want to insist that it was deliberately created this way
by a designer, then, well, we certainly can’t call this designer intelligent…
Now the fourth and fifth lines of evidence I’m going to present both come from DNA
sequencing, which for those you unaware, is the process of determining the precise order
of nucleotides within a DNA molecule, which put simply means that we can compare the DNA
of one organism to another, and in doing so, see exactly how closely related they are.
Needless to say, by doing this we have made many outstanding discoveries, but perhaps
the most extraordinary, and what I offer as a fourth line of evidence, is that all living
things are related, and that therefore all living things share a common ancestor.
Seriously, of the DNA that is comparable, you share 97% with a chimpanzee; 80% with
a cow; 60% with a fruit fly; and 50% with a banana.
Now most of us have heard this fact before and treated it like it’s just a bit trivia
(including myself), but it’s far more than this – it’s unimpeachable proof that all
living things share a common ancestor, and considering that all living things don’t
look the same, it’s also overwhelming evidence of evolution.
And the second line of evidence from DNA that I’ll present (and is the fifth within this
video), is that the closest living relative to cetaceans (which is a class that includes
whales), is the hippopotamus, a land mammal that just so happens to share many very rare
commonalities with cetaceans.
For example, both mammals are nearly hairless, do not have sweat glands, have remarkably
thick bones, are encased in dense fat, have multichambered stomachs, give birth to their
young underwater, feed their young under water, and communicate with their kin under water.
Now all of these similarities once again make perfect sense if cetaceans and hippos share
a common ancestor (as their DNA screams, let alone suggests), but if they didn’t evolve
from a common ancestor then all of these similarities are one hell of a coincidence, and DNA is
greatest troll in history!
The sixth line of evidence I’ll present is the artificial selection of domestic dogs.
It’s no secret that most breeds of dog have the specific traits that they do because humans
have deliberately (or artificially) selected which dogs get to reproduce, and in doing
so, which traits are passed on to subsequent generations.
For example, greyhounds have powerful legs, deep chests, flexible spines, and slim builds
because humans have deliberately bred dogs with these attributes.
The same is true of the tiny height of Chihuahuas – they are the result of humans breeding
smaller and smaller dogs; and the same is also true of the giant height of Great Danes
– they are the result of humans breeding bigger and bigger dogs… it may not seem
like it, but domestic dog breeds alone not only suggest evolution, they demonstrate it.
Now as we’ve just explained, the selective pressure in the case of domestic dog breeds
is artificial – it’s humans deliberately selecting which dogs get to reproduce – but
this raises the immediate question of what exactly selects which organisms get to reproduce
in nature, and the answer is… nature.
To further explain this, and to give you a few fascinating examples, I’m going to have
Thomas from Holy Koolaid jump in – enjoy!
This first example is a bit of a celebrity in the world of evolutionary biology – the
peppered moth.
During the industrial revolution coal plants dumped out enough pollution to kill the light
coloured algae in the trees, and coat the foliage in soot.
The light-grey moths, which once blended in against the bark of the trees, were now exposed
and were picked off by birds and other predators.
But a small percent of the population had a rare genetic mutation that lead to dark
coloured wings.
This beneficial mutation have them a survival advantage, allowing them to camouflage in
with their environment.
Before long, the majority of the population were the darker variety, but in the 1950s
clean energy reform reversed this trend, causing the dark moths to be more venerable, leading
to a reassurance in the lighter covered moths, who were still the dominant variety in the
less-polluted country-side.
Now that genome sequencing has becoming available and affordable for scientists, researches
at the University of Liverpool have pin-pointed the exact mutation that caused the colour
change.
Another excellent example of evolution in action is the Silent Cricket of Hawaii.
To, attract a mate, male crickets on the island of Hawaii would rub their wings together to
create a chipping noise.
Several years ago a parasitic fly entered their ecosystem, homing in on the noisy crickets
and laying inside of them that will eat them from the inside out.
A rare mutation on the x chromosome caused some crickets to develop without the ridges
on their wings required to chirp.
Natural selection did its thing, and within just 20 generations 95% of the crickets on
the island were silent.
When the flyers migrated to Oahu a few yeas later, the crickets there underwent the same
life-saving evolutionary change via a different mutation.
Now that’s all fine and dandy, creationists might argue, but those are all examples of
microevolution, not macroevolution – animals never chance species or reproduce outside
their kind.
Which brings us to ring species.
For this, we’ll take a look at the Greenish Warbler of the Himalayas, which biologists
believe migrated south to north, branch east and west, around the mountains.
As time passed the evolved and adapted to their new environments, but by the time they
met up north of the Himalayas, they were so different that they were no longer able to
inter-breed.
Each bird reproduced with its southern neighbours all the way back around the loop, but they
couldn’t reproduce with each other.
A textbook example of evolution in progress, if I’ve ever seen one.
Thanks for those brilliant examples Thomas – as always, you’re on form Sir!
Now I assume that many of you already knew who Thomas was before seeing this video, but
for those of you who didn’t, I implore you check out his wonderful content.
He’s a remarkably talented creator and a true asset of rationality.
And when you inevitably decide to subscribe to him, do me a favour, and let him know who
send you.
Anyhow, before I go, I’ve got another treat for you, and it also includes Thomas – in
fact, it stars Thomas!
If you click on this link you’ll be taken to his channel to see the counterpart of this
video, titled “10 Misconceptions about Evolution”, and within it you’ll see both Thomas and
I go to town on many of these aggravatingly ignorant misconceptions.
And so, my fellow apes, what’re you waiting for?
Click the link and join me over there!
You’ll be pleased that you did!
Oh, and as always, thank you kindly for the view.