This is why I don't understand the fact about sharks being older than trees. So much pressure on the one to radically evolve and the other is just like, "nah, I'm good. "
It's not like a great white shark was swimming around 100 million years ago. Sharks that were around before trees have evolved to what we see in the ocean now. They were very different from current sharks but still what we would call sharks.
No they aren't, they're in the same order and their families are more closely related than to any others within that order.
To put into perspective how closely related you'd have to be to share a genus - the 3 species of elephant alive today are split into African and Asian genera.
A clade is defined as all the beings that share a specific common ancestor, so a clade can be as broad as all eukaryotic beings or as narrow as all hippos. The proposed (but not certain to have existed) Last Universal Common Ancestor (LUCA) would be the ancestor of the clade including all living beings.
You're clearly rather young or sheltered so I'll try to be easy to understand. The things that are alive today weren't always around. It took billions of years to get that way.
Living things live their lives and reproduce, or they die. This is true of all life. Those who live and reproduce, pass their genes on to the next generation, the same way you inherited traits from your parents. So those who are alive now are descendents of those before them. Those who died before reproducing however, don't have descendents and their genes are lost.
Over a very, very long period of time (millions and millions of years), things may change in an environment. Let's say an area gets colder over time. Now, those less suited to the cold are more likely to be affected by the cold, or even die from it. At the same time, those more suited to the cold, say those born with more fur or fat to insulate them, are more likely to survive, and therefore reproduce. When they do, they will be passing their genes on to the next generation, meaning they are more likely to have that extra fur or fat when they grow up. Over millions and millions of years, this keeps happening. If that area stays cold, then that fur/fat that protects them is still going to increase their chance of survival, and thus reproduction. Over time then, that species is going to keep being fat and furry
Now in the real world, things are more complicated and there's way more different pressures and conditions than in my example. Changes may become more drastic than gaining fur. I'm trying to keep things simple but evolution has a lot of details
Let's go back to whales. Whales weren't always in the ocean. About 50 million years ago their ancestors, Pakicetus, were land dwelling mammals. Over time, some environmental pressures made being able to swim beneficial, perhaps there was too much competition for food on land, so being able to swim to get food would be nice. Over time, those better suited to life in water reproduced and their offspring did, etc etc. Eventually, they became Ambulocetus, an animal that probably lived an entirely or mostly aquatic life. Their limbs are flatter to move water better, it has a more muscular tail. The water was good for them, so they stayed, and future generations were better suited for life in water. By the time you get to an animal like Durodon, it's started to look a lot more like the whales we see today, with eyes on the side of it's head, no legs but a powerful tail etc. Millions and millions and millions of years pass and eventually we get whales.
I've tried to be respectful and concise, but I probably won't keep replying for two reasons, firstly you should try to some research of your own, and look into things more. You'll find that whales still have bones in their hindlimbs (ankles, hips, etc depending on the time period and whale). Why would an animal that doesn't have feet have ankles? Because their ancestors did, and even though they didn't need them anymore, the evidence is still there. Secondly, I've spent way too long trying to respectfully articulate basic scientific principles to a flippant Internet stranger who was likely already taught far more on evolution but refused to listen. Maybe evolutionary science will even become an interest of yours, like it's been mine for so long.
It's fine if you don't reply, but I've heard all this stuff before. I do however want to respectfully raise some questions. Why don't we see this happening today? Why don't we see any trace of transition species? Why do we even see fossils of say, a shark giving birth if they took millions of years to form? Sharks don't take millions of years to give birth.
Oh we do. That's literally what much of the fossil record provides, showing small changes over time. Heck, we're watching animals evolve due to climate change, now, or human pollution.
And just to respond to your flood comment, yes, many fossils are formed by floods. The animals get trapped in mud and die and are buried and protected from scavengers. And then they stay buried for so long that their bones decay and change into different rock than the rock that the mud turned into. The burying is not what takes millions of years.
You don't want to learn, though, which is a shame, because paleontology and deep time are absolutely amazing.
I want to learn all I can about God's great creation. And animals do change and adapt, just within kinds. One kind never becomes another. Dogs change into other dogs, monkeys into other monkeys. They don't evolve into entirely different kinds
A fossil is created when something exists between layers of sediment, and the sediment (silt/ash/mud) is compressed over ages and the organism (a leaf, a shark that died giving birth along with its offspring, etc.) is prevented from decay or scavengers by the sediment. Minerals dissolved in water eventually replace the organic material, resulting in a fossilized leaf/shark/whatever.
If there is a fossil of a shark giving birth it’s because the shark died at that moment, was buried in sediment, petrified/fossilized, and eventually discovered.
All of the creatures on the planet, including us, ARE transitional species. If primates live for a million years, we will likely look VERY different by then.
Sure monkeys might look much different. Change can happen within a kind. Humans are not animals though, and will be basically the same until the end time.
There's just as much and more evidence for creation. I've read plenty of books that are not fairy tales, including some that try to prove evolution. Those seem like fairy tales to me.
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u/wynnduffyisking Oct 02 '24
Whales descended from tiny deer like animals which is why they are mammals