Zimmer

"The lineage that gave rise to dolphins, whales, and porpoises went through a transformation just as staggering as the one that brought vertebrates on land in the first place; about 50 million years ago a race of wolflife mammals began to adapt themselves to water. They lost their hind limbs altogether and turned their back on the place that had been their ancestors’ for over 250 million years."
Carl Zimmer "At the Water’s Edge

* * * * *

I once knew a fellow who told me that he had, when younger, spent a lot of time in the sea, surfing and swimming, and he began to notice something odd around the throat area. The man said he went to see a specialist who told him he was growing gills and it was suggested that the man stay away from sea water if he wanted to get rid of them.

Now you’re probably going to say – "Honey, this fellow was having a lend of you". Maybe, maybe not, but whether or not the story is true, the internet has been abuzz since 2004 with this news -

"The human parathyroid glands, which regulate the level of calcium in the blood, probably evolved from the gills of fish …"

"… A team from King's College London believe that they were internalised, rather than lost, when four-limbed, land-living animals evolved."

"… "… new research suggests that in fact, our gills are still sitting in our throats - disguised as our parathyroid glands."
http://news.bbc.co.uk

So though this information doesn’t exactly verify the story above, maybe it doesn’t sound quite so silly as on first mention.

From the same source as above,

‘Researcher Professor Anthony Graham said: "As the tetrapod parathyroid gland and the gills of fish both contribute to the regulation of extracellular calcium levels, it is reasonable to suggest that the parathyroid gland evolved from a transformation of the gills when animals made the transition from the aquatic to the terrestrial environment.’

As dolphins, whales and porpoises have done, is it possible that humans (I'm not saying all humans, but some humans) - over many many (many many many) generations - might morph back into under-water creatures?
----------------------------

Mermaid Picture: http://lair2000.net/mermaid39/mermaid39.html
and turn up the sound!

Mammals evolved on terra firma ...

While I was reading articles on the internet, this statement took me by surprise.
"Mammals evolved on the land".
I knew that. Didn’t I? To be honest I’d never given it any thought. Which is likely why the statement took me by surprise.
But of course they did.
However my eyes are newly open and I’m looking at life kind from a different place after I became aware – the other day - that there is scientific evidence to prove that predecessors of whales (and dolphins actually) once lived outside of the oceans.
Although all along there was a clue to this - in the dictionary.
Possibly any dictionary will offer a similar definition, and in the Oxford it says, besides humans, mammals "include dogs, rabbits and whales".
Keeping in mind the assertion that mammals evolved on the land, there is an implied message in that short list that the biology that gives (humans, dogs, rabbits), whales - and dolphins - their shared "mammalian-ship", today, was evolved on land. By which we can infer that those creatures that predeceased whales (and dolphins) were once land mammals.

A Whale of a Tale

This afternoon is the last day of my holiday and tomorrow I head back into the salt mines so I’m really working hard at relaxing now.
I was reading the following in the Reader’s Digest Book of Facts and suddenly I found myself on a book buying expedition.
The idea of an Evolutionary U-Turn grabbed me by the throat, read this ~
"The ancestors of whales were once land animals. Scientific examination of whale skeletons indicates that they have a vestigial pelvis or hipbone, proving that whales once possessed legs. The ancestors of whales, like the ancestors of all animals, came originally from the sea. But whales began returning to the sea about 70 million years ago, steadily losing the physical characteristics of land mammals.
Their front legs changed into flippers, their rear legs disappeared, their bodies acquired a thick insulating layer of blubber and their nostrils moved from the snout to the top of the head to become a blowhole.
It is not known why whales returned to the sea, but it may have been because food was more plentiful there or because enemies were fewer.
--------------
So what, you might say?
I didn’t say that, I put my imagination to work. But I felt suddenly blind as if I were stumbling around in the dark. The pictures wouldn’t come.
I didn’t have a problem with the idea of creatures evolving, that is old stuff for me and I do believe that the trend of lifekind is to change, to evolve.
It was just hard for me to think about a creature sustaining a painstaking biological change to adapt to living on the land only to revert back at some point to becoming, once again, a sea dweller.
And it’s not why where the problem lay, and it may not even be how - because I’m really quite used to not knowing anything about a lot of "stuff".
I think it boils down to an assumption I made based on a prejudice I have. That having lungs is a sign of greater sophistication and complexity; so a surer sign of intelligence and superiority than having gills.
Hell bells, I thought. I’m something that there’s not a word for, yet.
I’m a sea creature-ist!
For years I’ve clearly seen in my mind’s eye, a one way lineal march of creatures moving from the sea and progressing to live on the land, I perceived that, from there, a "natural" extension would be for any terrestial life-form worth its salt to find the means to move from the land and travel into space - and the final frontier – not necessarily humans – I’m not an animal-ist.
I just didn’t expect that any creature would turn tail, and retreat back into the sea!
And yet the crazy thing about that vision is, a land creature is no better adapted to living in space than a sea creature would be. I think we can probably learn every bit as much from whales as they can learn from us.
Anyway to soothe my troubled mind, I went on the net, the biggest playground cum market-place ever.
I found, "At the Water's Edge, Fish with Fingers, Whales with Legs, and How Life Came Ashore but Then Went Back to Sea".
Yes, I thought, I would like to know about the "…engines of macroevolution .." and "… the transformation of body shapes across millions of years."
So I have now bought the book and I’ll blog you about it .. later.