@shadowsonawall Thanks I'm glad you enjoy the series. I think I understand what you're asking, but if my response doesn't answer your question, please let me know. Note that evolution occurs in groups, and usually full on speciation occurs over many generations. For example, Canis lupus familiaris (domestic dogs) can mate with Canis lupus (Gray wolves). Modern domestic dogs are descendants from ancient wolves. (We used to think that they were descended from Gray wolves, but later research refuted that). For another example, there's evidence that Homo sapiens (our species) mated with both Homo erectus and Homo neanderthalensis, both considered transitional forms on the way to humans. Did this help?

@skepticsalamanderacct it more muddied the definition of species for me than helped 😆

I think you've got the right idea though. We have evidence to suggest that sapiens, erectus, and neanderthalensis were all sexually compatible. Similarly, we know that dogs and wolves are.

Dogs and wolves are particularly interesting imo. We (humans) have put incredible evolutionary pressure on the species. You used bugs to show variations - they've got nothing on dog breeds! I don't know of any break in sexual compatibility between them though.

@shadowsonawall Can you perhaps rephrase your original question? Thanks!

@skepticsalamanderacct no problem! (Sorry I'm not explaining it well)

How do you get a new species? It seems like the next generation would always be sexually compatible with the current generation. The best I can figure, if a member weren't, they'd be sterile, not a new species.

@shadowsonawall Speciation occurs when a group within a species separates from other members of its species and develops its own unique characteristics. The demands of a different environment or the characteristics of the members of the new group will differentiate the new species from their ancestors.

This takes a really long time however. An example is the evolution of ancient land mammals (artiodactyls) to whales.

And there's a breaking point in which a species can no longer breed with an ancient ancestor. We don't know how far back that is. It could be over 1 to 2 million years ago for that breakout point in Hominins. For example, I doubt that we could have bred with Australopithecus afarensis.

@skepticsalamanderacct yeah, that's the answer I've heard/given 😞

"macro" evolution (speciation) is very challenging to defend.

@shadowsonawall Don't let creationists fool you. They love the terms "microevolution" and "macroevolution," but in reality evolution is just an ongoing process.

Given enough time, it makes sense that small changes will turn into big changes. If you start at the color orange and move about the color spectrum, it's not going to become different shades of orange forever, it eventually is going to become red.

No scientist takes creationists seriously. They are agenda-driven by their religion and anti-science.

I recommend "Why Evolution Is True" By Jerry Coyne. Great resource.

Also this is a great (and huge) resource -
http://www.talkorigins.org/indexcc/index.html

@skepticsalamanderacct thank you for the resources! I like the analogy of colors but it won't hold under scrutiny 😞

The micro/macro evolution terms are pretty defensible. They are basically a "demonstrated" vs "hypothesized" distinction. Flung around in all kinds of ridiculous ways, for sure, but valid in that they do call out two distinct categories of evolutionary theory (not process).

I didn't mean to drag you down a rabbit hole, by the way. I just saw your videos and your fighting pseudo-science note and thought you might be able to help with a long running philosophical debate I'm in

@romandlg Thank you so much friend!