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.
Micro evolution IS macro evolution... Just over a longer period of time.
Everything in life can digest sugars. There's actually rules in bird-watching not to give white bread to eagles and hawks, because it's bad for them... Because they'll eat it. And like it. Because it's simple sugars. On the converse side, deer and chickens will eat mice, even though its out of their usual, it's a good source of protein.
So here's one of many possible hummingbird paths: Standard bird begins: Flies okay-ish, two eyes, two wings, one beak, two legs, you know what "bird" looks like.
"Bird" does not spontaneously transform. As you say, the beak gets slightly longer. Why? Flowers attract bugs. Bugs are good protein. Longer thinner beak means get to eat more bugs hiding inside half-closed flowers. Minor variation cemented over a couple hundred years. Flower needs bugs to pollinate, though. So flower that attracts more bugs, becomes dominant. How? More sugar. Sugar is the basis of all life... Somewhat. "Long-Beak-Bird" that can drink some of the sugar while also eating the bugs gets more energy, more energy = good. ALL life digests sugars. In fact, all life transforms what they eat INTO sugars, so just taking in nectar, which is close to sugar, is great. So Long-Beak-Bird would like to get extra nectar while eating bugs, but the nectar-rich flowers spray it all over the ground when they land on them. Smaller long-beak-bird needed. More agile long-beak-bird needed. Some are fine, and they branch to a different evolutionary branch. Others continue to mate with smaller and more agile mates that live longer since they get more nectar.
Small-agile-long-beak-bird still isn't a hummingbird, but it is closer than "bird". Lets introduce a problem to the environment: Bugs running out. Maybe the world got colder, maybe a new predator arrived, maybe too many small-agile-long-beak-birds bred and ate too many bugs. SALBB now have flowers with excess nectar, since the bugs aren't eating it, but less bugs. The ones able to keep flying with less protein are more likely to survive to mate. And being agile becomes even more important, since with the flowers overflowing with nectar, you get a lot more from them if you don't dispose of them... And being even smaller still is important with less protein to keep your bulk up. The ones able to process the sugar better survive. Others either die off, or branch to a different evolutionary branch. SALBB now primarily eats nectar, minimal bugs. It's also tiny, not small. Tiny-Agile-Long-Beak-Necter-Bird, TALBNB. But it needs one more notable trait before TALBNB becomes Hummindbird. A bird that can slow itself in flight is better at flower sipping than that one that can't. (crash into flower slower, less nectar spillage) A bird that can slow itself MORE is better than one that can only slow a little. A bird that can briefly slow momentum to the point of stopping for a moment mid-air? Even better. Hover? It's the same thing, just better at it. Hover... backwards? One that can mildly go backwards even just a tiny bit and slowly is hugely better at getting to new flowers on a branch, able to progress along an entire tree branch of flowers instead of taking a flight for each one. If they can go backwards faster, though, they can dodge predators with it.
And now you have an omnidirectional, agile, tiny, long-beaked, nectar-drinking bird. A hummingbird. All through micro-evolution. Whether or not that's the path "Bird" took I don't know, but off the top of my head I could see that path existing through only minor changes and a couple thousand generations.
Not a single fossil of a transitional species ever found.
No explanation of cambrian explosion
micro and macro are not the same. that is just a stupid statement.
Embarrassing to see this upvoted here lmao
https://www.youtube.com/watch?v=UuIwthoLies
Aww, you didn't even CARE about my wonderful theorization of hummingbird growth!
Sure they have. God of the gaps argument, yawn. Every single fossil is a transitional fossil.
When lots of ecological niches open, things grow into those niches. That is how you'll have two very different species occupying the same niche in different locations: The niche was open, so something wound up taking it.
Micro and macro are merely levels of scale. Microeconomics done ten thousand times is macroeconomics. Microevolution done ten thousand times is macroevolution.
But you're not here for a good... "faith"... conversation. Ah? See what I did there? ACKNOWLEDGE MY PUN!
What you're missing in all of this is each of those variations would take more iterations to reach a 50% probability of arising by pure chance than the total number of generations.
"Oh, just stack up a billion billion-to-one-odds mutations" is not a rational explanation when there have only been a million generations.
"Thing with longer beak can reach things it likes to eat better than thing with shorter beak, even if it is just 0.01mm longer each generation" is hardly "billion-to-one odds mutation".
That's like saying "tall people tend to have tall kids, and dwarfs tend to have dwarf kids? Billion-to-one odds! Billions-to-one! Tiny asian parents have seven foot tall black kids all the time, the odds of a tiny asian parent having tiny asian kids is zero! ZERO!". Longer-beaked birds tend to have longer-beaked chicks.
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.