Charles Darwin Galapagos tortoise | Charles Darwin's Theory of Evolution by natural selection

Charles Darwin Galapagos tortoise

Tortoises of the Galápagos

All saddlebackedThe Galápagos archipelago is a group of volcanic Pacific islands located on the equator, 972 km west of continental Ecuador. They are probably most famous for Darwin’s historic month-long visit on the Beagle in 1835. The strange creatures that Darwin reported on, such as the birds and marine iguanas, have fascinated readers since. But the iconic species is the native giant tortoise, from which the archipelago receives its name (see ). The largest living species of tortoise, the Galápagos tortoise can weigh over 250 kg (550 lb) and live for over a century.

Darwin and the tortoise

Charles Darwin studied the tortoises, and the islands’ vice-governor told him that one could tell from its characteristics alone which island a tortoise was from. Darwin initially dismissed this statement, and rightly so, since even modern evolutionists admit that it was something of an exaggeration. So he took the differences between the varieties of tortoises to be nothing more than the sort of variation which could arise from a species being transplanted to a different habitat. But he failed to take detailed notes of the variations among the tortoises (his notes mostly record their behaviour) or to take specimens for scientific study.

The Galápagos tortoises were subject to overhunting by humans who kept them for food on ships. This decimated the population. The giant tortoises were seen to be an excellent source of fresh meat, as the tortoises could be kept for long periods of time with little food or water. The sailors on the Beagle took 30 on board for this purpose, discarding the shells and bones as they consumed them. (Woodmorappe suggests this as one more possible food source for carnivores on the Ark; fodder tortoises.)

Darwin took two young tortoises as pets. And they, along with specimens Captain FitzRoy took for the British Museum, constituted Darwin’s only evidence when he realized the tortoises’ importance.

Varieties

Over 10 sub-species have been identified (four of which are extinct), because they have distinct physical characteristics. But they can all interbreed with one another, so they are classified as one species of tortoise, Geochelone nigra.

Diagram showing in principle how several tortoise varieties can arise from one, simply by sorting already-existing genes via natural selection. For example, the smaller islands tend to be drier, so they don’t support much grass; the only vegetation is cactus and shrubs. So tortoises with saddlebacked shells that can browse will be able to eat, while domed tortoises starve. Thus the only tortoises to pass on their genes to the next generation are the saddlebacked ones.

See also:



RIP: Galapagos tortoise

by CropCircles


QUITO, Ecuador (AP) - Giant tortoise experts from near and far have begun an autopsy of Lonesome George, whose failed efforts to reproduce made him a symbol of disappearing species.
The Galapagos Island reptile was the last of the Pinta island giant tortoise subspecies and he was found dead in his pen on Sunday.
He had become an ambassador of sorts for the archipelago off Ecuador's coast whose unique flora and fauna helped inspire Charles Darwin's ideas on evolution.
Galapagos conservation official Washington Llerena says scientists suspect Lonesome George died of a heart attack

Boycott the pussies - Let religious fanatics Win

by piecewore

Darwin exhibition frightening off corporate sponsors
An exhibition celebrating the life of Charles Darwin has failed to find a corporate sponsor because American companies are anxious not to take sides in the heated debate between scientists and fundamentalist Christians over the theory of evolution.
The entire $3 million (£1.7 million) cost of Darwin, which opened at the American Museum of Natural History in New York yesterday, is instead being borne by wealthy individuals and private charitable donations.
The Darwin exhibit features a live Galapagos tortoise
The failure of American companies to back what until recently would have been considered a mainstream educational exhibition reflects the growing influence of fundamentalist Christians, who are among...

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Charles Darwin and the secrets of the Galapagos Islands  — ABC Online
The Galapagos Islands are famous for their abundance of wildlife, which inspired Charles Darwin's theory of evolution. Robyn Williams retraces Darwin's footsteps and discovers that not all that much has changed off the coast of Ecuador.

The Galapagos Tortoises: Nomenclatural and Survival Status (Contribution No. 199 of the Charles Darwin Foundation for th)
Book (Chelonian Research Foundation)

FAQ

nikkiii
Charles Darwin......?

I have to do a paper for my science class on charles darwin. it has to be in "news paper clipping of that time" form. meaning i have to write about something significant he did like i was a journalist from that time. but i cant really find anything clear enough for me to write 3 pages about. yeah, it's gotta be 3 pages long.

any ideas?
it'd be much appreciated.

Really??? Darwin is credited with Evolution, Evolution has redefined science. His discoveries with Finches that he compiled when he got back from his trip on the HMS Beagle is a good place to start, or maybe his Eureka moment when he was reading Malthus and was able to put together evolution into a coherent idea. Those are two of literally tons of things that would work. 3 pages is an easy assignment!

Laura G
Grammar - is an abstract concept 'personified IN' or 'personified BY' a person?

I'm writing an article where I'm saying that the quote "genius is 1% inspiration and 99% perspiration" could easily be personified by Charles Darwin. 'Personified by' sounds ok to me, but is 'personified in' the technically correct phrase? Basically, I'm trying to concisely say that Charles Darwin's life is a good example of that quote, as there was no "Eureka!" moment but a long slog of research (several decades, in fact!) to come up with his theory of evolution. I'd really like to know how I can tell when to use 'personified by' or 'personified in' (so that I can get it right in…

This may be easier to understand if you first express the sentiment in the active voice:

-- Charles Darwin personifies this quote.

Changing to passive voice yields the structure in question:

-- This quote is personified by Charles Darwin.

In the passive voice, the element that was the subject in the active voice commonly becomes the object of the preposition "by".

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