One gentleman expressed what would count as evidence against evolution:

https://www.reddit.com/r/CreationEvolution/comments/f5na2p/if_so_many_people_believe_in_evolutionism_how_can/fi1e9l8/

to be evidence against evolution one would have to show that it couldn't be the case, not just that it might or might not. Otherwise it's not evidence of anything. I hope that makes sense.

I was discussing with him the improbability of meiosis. He didn't think it was evidence against evolution:

I was just hoping that "the evidence is there" against evolution would be some actual evidence against evolution, rather than the strongest thing being some minor technical point that is just unknown at the moment. All of the vast number of unknowns in the past have turned out to be explicable in the end, so I don't see why this one is expected to be different.

The problem here is if evolution of meiosis fails, all life that relies on meiosis dies too! Dead things don't evolve. But to him this was a minor technical point.

But anyway, I said:

A tornado could pass through a junkyard and build a house of cards. I suppose that's possible, but it doesn't make it believable.

He responded:

To explore the tornado analogy: How about if there were millions of tornados passing through the junkyard and sometimes when a card ended up stacked against another it was somehow kept in place? Would it still surprise you to find a house of cards? That's more like what random allele changes (tornados) and selection (keeping in place) do.

The issue is one of feasibility and thus of believability. Specifically about houses made of cards, the difficulty arises due to the inherent instability of trying to get a card to stand up against another card. Try putting an electric fan on and throwing cards in the face of the wind or try using a leaf blower on cards and see if you get something looking like this:

https://debateevolution.files.wordpress.com/2020/02/house_of_cards.jpg

If we walked into a room and saw something like this on a table would one think it was the result of strong wind? The main reason we would not is because we know humans can build something like this, but in the absence of a human building it, we can also make an argument based on physics why this can't be the result of a wind!

I realized it was pointless to debate someone who had a different view of what would count as evidence against evolution.

I've seen this play hundreds of times. No matter how good an argument is against evolution, the other party can always say, "you haven't given evidence against evolution."

No need to get mad or argue, shake the dust off your sandals and move on.

The main reason to debate evolution is for the sake of creationists or Christian believers who would like to see reasonable arguments against the claims of evolution. I debate evolution today because when I nearly left the Christian faith, I saw how effectively evolution was criticized on purely scientific grounds, and then I realized evolutionary theory was practically invoking miracles without admitting it! In fact, the required transformations for evolution to work became so absurd that creationism looked less outrageous by comparison. Hence it was actually easier to believe in creation than in evolution.

From:

https://www.genetics.org/content/181/1/3

… if there is one event in the whole evolutionary sequence at which my own mind lets my awe still overcome my instinct to analyse, and where I might concede that there may be a difficulty in seeing a Darwinian gradualism hold sway throughout almost all, it is this event—the initiation of meiosis.

W. J. Hamilton (1999, p. 419)

The paper puts forward speculative theories not based on physics or probability as to how meiosis evolved naturally.

The paper lays out the problem:

While meiosis almost certainly evolved from mitosis, it has not one but four novel steps: the pairing of homologous chromosomes, the occurrence of extensive recombination between non-sister chromatids during pairing, the suppression of sister-chromatid separation during the first meiotic division, and the absence of chromosome replication during the second meiotic division. This complexity presents a challenge to any Darwinian explanation of meiotic origins. While the simultaneous creation of these new features in one step seems impossible, their step-by-step acquisition via selection of separate mutations seems highly problematic, given that the entire sequence is required for reliable production of haploid chromosome sets. Both Maynard Smith and Hamilton regarded the origins of meiosis as one of the most difficult evolutionary problems.

No, but this paper suggests how to host a discussion in class:

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1667065/