Also, obviously if the Christian God is real He can do whatever He wants. Any God can do whatever they want pretty much, unless it's a pantheon where gods fight or something. If you think this is all a dream then whoever's dreaming it can do whatever, at least if they're aware. If you've seen the Haruhi anime, Haruhi can perform whatever miracles she wants. All religions believe God can do whatever they want, and that's just sensible. They're God.

God could obviously spawn as much water as He wanted. He could make pocket dimensions or something in Noah's ark. It doesn't even really matter.

You do raise another good point though, which is essentially that you think Christianity contradicts evolution. Obviously if you're a creationist then that isn't a problem, but most Christians nowadays are not creationists.

What would really need to be proved through evidence of evolution in order to discredit Christianity is exactly what you said. "Mankind isn't descended from two people."

Evolutionists are often discovering "gaps" in their chain, and by that I mean filling them in. I don't think the gaps in the evolutionary lines disprove it. That's just totally stupid. There's a futurama clip where they explain how dumb creationists are to think that, and I totally agree with it.

The problem though is that essentially evolutionists just discover snapshots of evolution. Pretty sure I had evolution explained to me in my biology class as the evidence being like this: take a photo of your dad and one of yourself, then if you have any children tell them to do the same and collect them up in a big photo album. Over the massive timescales of evolution, you should start to see some change or development in these pictures. You should in theory be able to start with very simple microorganisms and create a family line going all the way down to a modern human, but they can't do that in practice.

The lineages worked out based on fossils by scientists aren't even as clear cut as that. If I discovered the bones of some neanderthal and named them "Alice" or whatever (I don't actually know all the lineages in detail, but schools will often teach a small segment leading up to Homo sapiens, and I used to have that memorised), then someone else found another set of bones and decided to name them "Bob", we could start talking about Alice and Bob.

Alice and Bob were essentially people. They weren't as evolved as modern people but they were both prototypes of a person at some stage in human evolution. Alice and Bob probably weren't close family members. It's exceedingly unlikely Alice was Bob's mother or sister. If they were found in the same region and dated to a similar time period then they should be quite similar, and that's generally what evolutionists find. You can also analyse other things, like most obviously the shape of their bones, which changed over time. There are more advanced things evolutionists check in modern times too, like they compare the genetic codes for cytochrome oxidase, since it's an enzyme found in pretty much all life. That may not have been preserved in some of these fossils though, idk really tbh.

Bare in mind of course that most people didn't end up as fossils, and most of those probably haven't even been found and analysed.

The actual point is that at no point could we say Alice and Bob were in any very easily understandable way related to one another, nor do we know exactly who their ancestors are. Evolutionists (scientists) sketch out big trees that show how creatures at different stages of evolution were related to each other based on various evidence. Their evidence will always be incomplete in that they can never ever trace an exact lineage from a million or so years ago.

There could be an older fossil, Charlie, who they put in as part of their tree because he seemed like an earlier stage and more similar to the stuff/people that came before him. Charlie could have died from some genetic disease and never had children though. He might have been an evolutionary failure. An actual evolutionary scientist would likely be quick to correct you if you said Charlie was "the ancestor/father" of Alice or Bob.

What I'm trying to say is, evolutionary scientists would have no way of knowing "mankind isn't descended from two people". They might say that's not generally how evolution works, but if you use a relatively small sample and evolve antibiotic resistance into bacteria, it would technically be possible. It might even have been happening exactly like that occasionally across the world when hospitals didn't realise there was such a problem with antibiotics and how they should be prescribed.

Essentially, there's a small chance/it is theoretically possible we evolved from two people, especially after a big extinction event.

Every Christian who isn't a creationist should be aware of the fact that the term translated to "day" in most English versions as in "God created the world in 6 days, then rested on the 7th" or whatever doesn't necessarily mean "day". It could just mean any arbitrary time period.

If we're gonna go extra far with how evolution could fit in with the Bible, we could say some of these "days" corresponded to different parts of our huge scientific time period.

Maybe God brought about Adam by perfecting the genetic code miraculously after a major extinction event long in the past, and humans evolved from there, though the lineages in the Bible would disagree with this. I think a more sensible view for a non-creationist Christian would be that Adam was a very late stage in human evolution (probably actually Homo sapiens). God could have created Homo sapiens by making some changes to the previous step, which would be somewhat consistent with being made in "His image". That would be a literal interpretation.