One of the more cunning disputes of Creationists is the quibble over what is a “kind”. Does a Lion and a Tiger represent 2 kinds? Or are they in fact just ONE kind of “big cat”? Well then, is a domestic cat PART of this ONE kind? Who really knows…
But in the history of Whales … we can see MULTIPLE kinds! There was the land-based mammal. That’s certainly a kind.
But then this land based creature started hunting food in the water. Same kind, I suppose, right?
But then this creature started evolving into something more than an otter … he started to develop fins instead of arms.
Same kind now? And instead of his lungs connecting through the nose and mouth, this animals lungs started connecting through a shifted nose, at the top of his head! Still the same kind?
At some point, this creature stopped bearing offspring on land … and gave birth to them in the ocean. STILL the same kind? Hardly.
In the video from the link below, they focus all their Evolution discussion on the Whales !
The “Independent Lines of Evidence” slide below comes from the excellent video in the link!
The claim is that if you go back far enough (60M years), the common ancestor of whales and hippos and deer was a land-based mammal that, of course, had 4 legs. Sub-populations of that common ancestor diverged. The ancestors of hippos and deers stayed on land, so natural selection acted to preserve the legs from generation to generation. The ancestors of whales such as Pakicetus, however, began to hunt in the water. Natural selection favored more fin-like appendages. Over tens of millions of years, natural selection, in combination with DNA variation, gradually yielded fins.
The occasional appearance of (useless, vestigial) leg-like appendages on dolphins and whales would actually point to their having vestigial, non-coding DNA for legs present in their genome. Occasionally, a mutation causes that DNA to express, and vestigial legs appear. This is extremely rare, but it has been observed in the wild.
So the question is: why would dolphins and whales have vestigial, non-coding DNA for legs present in their genome?
The dolphin story is not the story used by scientists to bring up the topic of limb-like structures embedded in the body of cetaecians … and NOT visible to anyone while the creature is alive.
again-the function doesnt have any conection to legs but to fins. as we can see from the front limbs. also notice that the pelvis of male and female whales are different. and now we know that it even have a function other then swiming:
If the bones are shaped like fins … so be it. But if they are shaped like legs… you are just distorting the reportage. Find an article about “so-called” leg bones in Whales that say they look like FIN bones instead. Then we can discuss it.
Otherwise, you are just intentionally throwing dust into the air.
@dcsccccc - I misremembered the scope of the atavistic legs; they are only present in whales, not dolphins.
First, let’s take a look at the evidence for atavistic legs (not fins) in whales. I will be quoting several reports; follow the links, and you will see photographs/figures.
In 1958 we examined a male Sperm Whale 11.6 meters long caught in the Bering Sea, with unusual protrusions in the pelvic region and along the sides of the genital fold (see Figure #1) with a total length of 28 and 34 centimeters, pigmented like the rest of the body. The section of the left protrusion that extended from the body had the appearance of the rounded blade of a propeller, while the right one looked like a fin with finger-shaped processes. The bones were enclosed in dense connective tissue. Judging from an X-ray photograph (see Figure #2) of the skeleton of the protrusions in this specimen, the section of the protrusions that lay inside the body corresponded to the femur, and the middle section to the tibia and the fibula. The section of the protrusions that extended from the body corresponded to the step of the hind limb, and the elements composing it are probably phalanges of the digits. According to the number of phalanges visible in the X-ray photograph, these are the fifth and fourth digits.
This particular whale was a female Humpback of the average length with elementary legs protruding from the body about 4 feet 2 inches, covered with blubber about one-half an inch thick. As shown in the best photograph these legs protruded on either side of the genital opening…
Female Sperm Whale caught by Japanese whaling operation, Nov. 8th, 1956, “protuberances on both sides of the genital opening. … The height of the protuberance was 5.35 centimeters on the right side, 6.56 centimeters on the left side.” (SEE PHOTOS OF THE PROTRUSIONS FROM SIX DIFFERENT ANGLES, Fig. 5)
“Upon examining the interior of the left limb three partially cartilaginous bones were found. They correspond to pelvis, femur, and possibly to tibia, but no joints exist between them. Pretty strong muscles connect between femur and tibia. The tibia is 13 centimeters long for the greater part cartilaginous, and only partly ossified stick-like body with its distal end inserted into the skin of the hind-limb protuberance.
Not being an expert in cetacean biology, I am unable to tell you which regulatory gene(s) behave(s)abnormally to cause these atavisms.
"Nothing can be imagined more useless to the animal than rudiments of hind legs entirely buried beneath the skin of a whale, so that one is inclined to suspect that these structures must admit of some other interpretation. Yet, approaching the inquiry with the most skeptical determination, one cannot help being convinced, as the dissection goes on, that these rudiments [in the Right Whale] really are femur and tibia. The synovial capsule representing the knee-joint was too evident to be overlooked. An acetabular cartilage, synovial cavity, and head of femur, together represent the hip-joint…
You ask why would dolphins have atavistic fins while certain species of whales have atavistic legs… It’s important to remember that there is a lot of variation over time across large populations. It would make sense to me that some cetaceans (dolphin ancestors) would have experienced an evolution toward small hind fins while others (right whale ancestors) did not. Eventually, the hind fins did not provide enough function to justify the hydrodynamic drag, so they disappeared among the population that gave rise to the dolphins.
We aren’t talking about dolphins. And we aren’t talking about malformed fins.
We are talking about those modern whales which, without having ANY KIND of malformation at all … have LEG BONES within their body, which cannot be seen by ANYONE (except God).
And these leg bones are consistent with extinct varieties of whale mammals that actually HAD fully formed, or partly formed, legs (or shall we call them rear limbs.
First, I note that you have not addressed my chief point, namely that the (rare) appearance of atavistic legs in some species of whales provides strong evidence for the continuing existence of unused genetic code for legs, which in turn provides strong evidence for evolution. I want to give you another opportunity to address that point.
[quote=“dcscccc, post:18, topic:4419”] Chris: "Nothing can be imagined more useless to the animal than rudiments of hind legs entirely buried beneath the skin of a whale
dcs: but wait. i show its wrong actually:
[/quote]
You are very, very confused, my friend dcs. I’m talking about vestigial femurs and tibias, and then you present evidence for the usefulness of something else altogether, the pelvic girdle. Let me make it as clear as I can:
You are correct that the structure of the pelvis continues to play a useful role in whale anatomy.
You have not begun to address the strong evidence for evolution provided by vestigial femurs and tibias in some modern whales.
I am astonished that you would think that this supports your case, my friend dcs. The basilosaurus, which lived 40M years ago, was (perhaps) able to make use of the legs which were much smaller than those of its ancestors. Modern whales don’t have such legs, so the functionality of legs in a species that lived 40M years ago aren’t germane to today’s topic. You could go back even further, say 60M years, and state that the legs of the common ancestor of whales and hippos were very useful. Yep, I would agree–it lived on the land, and legs are useful on land. Doesn’t help your case.
Evolution has continued to operate over these past 40M years, and whatever function hind limbs might have provided to the basilosaurus was not enough to overcome the pressure of natural selection towards a more hydrodynamic design.
Endless Forms Most Beautiful by Sean Carroll, a biologist at the University of Wisconsin. Great book, you’d really enjoy it, dcs.
