A passage from Carl Sagan's book written 25 years ago
(media.kotakuinaction2.win)
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There's a difference between micro-evolution and macro-evolution.
Micro-evolution (a bird with a slightly longer or slightly wider beak, or a different color fur) is almost certainly a real phenomenon. It requires a single, slight change. Minor variations in genes combined with artificial, natural, or sexual selection can happen in a generation, and can be cemented in a relatively small number of generations.
Macro-evolution makes no sense at all, when examined through the lens of mathematics.
The odds of a hummingbird evolving from a seed-eating bird or an insect-eating bird are astronomical. Not only do they need to develop the new beak, but they also need to develop a new digestive system that can process nectar efficiently as a primary food source. The hummingbird must out-compete other birds while preserving each useless mutation across generations until all the necessary ones (fast metabolism, sugar-optimized digestive system, small size, nectar-drinking beak) are in place, while expending the energy required to support what are, for that intermediary, completely useless genetic features.
If one examines the number of possible DNA mutations and compares the immediately-lethal ones to the ones required to form a new organism (never mind the merely-pointless), the probability of successfully mutating is astronomical - and then the first member of the new species needs to be so wildly successful as to create future generations, either through a second astronomical chance occurring in a second member of the species, or for those traits to be sufficiently dominant as to dictate the form of its offspring.
To create the platypus through random chance mutation, we would need a new word to express the size of the denominator.
I just want to know how we go from Dire wolves - the canine Chuck Norris - to an ass scraping ugly demon spawn called the pug, complete with breathing issues and stumpy legs.
Yes, pugs do the ass scraping thing and no it wasn't my "dog".
Dire wolves died off with the rest of the megafauna during the last ice age. Smaller members of the old species required fewer scarce calories to survive, so everything big got small or died off.
As for the wolf > dog > abomination path, artificial selection is significantly faster than natural selection. If you look at the Russian fox experiments, it took about 50 years to create a domesticated breed of fox. That's a single human lifetime to change the nature of a creature - in another hundred years, they might be able to create a fox that doesn't stink, and then it would be pet-ready.