Friday, 16 November 2012

The Crocoduck Lives...

The other week someone made a joke to me about the crocoduck argument and I found myself wondering if anyone actually found it a compelling argument for faith.

For those who dont know the crocoduck is an anti-evolution argument made by creationists. Basically the argument goes that because there no intermediate species sitting between two different types or "kinds" of animal (like a half crocodile half duck) then there is no proof that evolution could create one species from another.

They refer to changes in species or in "kind" as "macro evolution" and they claim because no such strange half creatures exist that therefore there no evidence of it.

Everytime I encounter the argument all I can think of is the criminally poor education these people had in evolution theory. Did they never see a picture of the tree of life? It's a simple diagram and you dont have to be genius to spot that, like a real tree, the branches dont join up again after they've split.

The fact that this argument exists is a wonderful demonstrations of just how little the people using it actually understand about evolution or science in general... The fact that anyone raised in Australian could use the argument is evidence of a failure to graduate the second grade.

Q: If one species can change into another over time why do we never see anything like a crocoduck?

A: Because ducks did not evolve from crocodiles.

Seriously? How is that not obvious? How does someone who consideres this a valid question get dressed in the morning because I find it hard to beliefe they manage so complex a task on their own...

But birds did evolve from something reptilian, like dinosaurs. That is why the skin on their legs has scales... Why their bones are hollow... Why they lay eggs, and why they develop a tooth to help get out of the egg when they hatch just like reptiles.

Modern species, however, evolved in parallel, which is why it so fundamentally wrong to say that man evolved from chimps (and for the record proponents of evolution have never claimed this). Rather modern species of animals evolved from earlier species: Thus man and chimp evolved from the same ancestor.

But the crocoduck argument keeps getting brought out, like that one malformed example of hand made pottery your friends kid made, the one with no opening at the top and five spouts that doesn't hold water without it spraying out through a thousand tiny little holes. The one they keep trotting out to proudly show you and expecting you to say how wonderful it is without pointing out that it doesn't work and is full of holes.

But we do have proofs of biological shifts, and not just in the fossil records. In australia we have very famous living examples of the state that existed when reptiles started to evolve into mammals...

They are called monotremes (actually that is their taxonomical "order"), they are egg laying mammals and Australia has two types of them.

The first is the echidna, sometimes called the "spiny ant eater" they look a little like hedgehogs and fill a similar niche but are so drastically different in biology that they cannot be related.

The second is the platypus... My favourite because it is so incredible even compared to the crocoduck.

The platypus, has a duck like bill (actually just shaped that way as it's not a beak but is in fact bone covered in soft skin, it's body is covered in fur, males have a poisoned barb making them the only poisonous mammal ever discovered, they hunt for prey in muddy water by detecting the electrical impulses of the muscles of their victims like a shark, and the females not only lay eggs but express milk through the pores of the skin as they have no teats.

When the first examples where returned to europe, they were claimed to be a hoax... After all God would never make such a strange animal, would he?

Monotremes stands as a testament to the path evolution took from egg laying reptiles to warm blooded live birth mammals. They are not fossils, they are surviving forms and they survived exactly where evolution said they should survive, in those places in the world where conditions did not change, to favour another species  where no environmental condition forced then to completely evolve away from laying eggs.

The echidna and the platypus are not less evolved that we are, they are the result of just as many (if not more) generations. They have taken just as many years to evolve into what they are today as we have, the only difference is they had less pressure to change, less conditions favouring new variations.

Evolution has no goal, but it is not just random, it is random mutation filtered through "environmental pressures". An animal like the crocodile exists apparently unchanged for millions of years because none of the random changes and mutations that they developed as a species served them any better than the systems they already had. From this we can assume that no fundamental changes to the crocodile would give it consistent advantage or such changes are prevented from occurring by other environmental factors.

This is not hard to understand, change happens in increments, each increment must have some survival value compared to the previous state. That last part is critical and often overlooked, it does not mean that each change is objectively good, only marginally better by comparison to what already was.

The Koala is another australian animal, like most australian fauna it is a marsupial and carries it's children in a pouch, unlike most it's pouch points backwards. As the Koala lives in trees this would seem a very poor "design" indeed, until you realise that the Koala is most closely related to the Wombat. Wombats live on the ground and dig tunnels a backward pouch makes perfect sense for them because it stops dirt getting in when they travel and burrow.

The fossil record shows that koalas evolved from ground dwelling animals like the wombats, the habit of climbing trees and eating leaves is the newest part of their evolution, the backward pouch is a legacy from their ancestors. Why hasn't the pouch changed? it still might but while a ground dwelling animal can afford to drop a baby everyone once in a while while the opening of their pouch migrates over thousands of generations, a tree dweller may suffer more during this change.

The koala may never evolve back to a forward facing pouch because the incremental steps may not be better than the current mode, because evolution has no goals only environmental pressures and compounding changes over time.

Another creationist claim you will hear is that you never see an animal with a vestigial limb. No kidding they will claim that the bones in a whale skeleton that used to be hind legs still serve some purpose.

Again the fauna of australia comes to the rescue, this time with the Emu! The Emu has a vestigial arm, not a wing, an arm. It has no flight feathers, it does have a claw, but it also has no muscles or tendons. These limbs do nothing, can not be moved by the emu, cannot be controlled and serves no purpose what so ever.

These are the examples form my own country but other examples exist in both living examples and in the fossil records.

It's hard to see why or how the crocoduck argument survives. It's been described as an argument from incredulity but I think it's better described as an argument from total lack of education.

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