Why do green sunfish hybridize the most with other Lepomis?

I think it is because generally everything about them (Their mouth size/body shape, aggression, etc.) are simply keyed towards and extreme 'live fast, die young' way of life. Your opinions?

If true, it could be because they're a widespread species and opportunistic in their microhabitat use. Any perceived aggression on their part would have little if anything to do with it. Male pumpkinseeds or longears in the breeding season are every bit as aggressive in defending nest sites and larval broods.

When I was researching my sunfish presentation way back when, I came upon a reference that said that male greenies would just barge into a spawning of longears and join in.

It seems like a similar pattern to the little sneaker and female mimic bluegills that intrude on the spawnings of the bigger male bluegills. But since the longears are bigger and nastier, maybe they can just join in if they feel like it, without fear of getting chased away.

Don't know if you've ever kept them or not, but greenies are a lot nastier than most comparably sized lepomids.

If true, it could be because they're a widespread species and opportunistic in their microhabitat use. Any perceived aggression on their part would have little if anything to do with it. Male pumpkinseeds or longears in the breeding season are every bit as aggressive in defending nest sites and larval broods.

In my experience green sunfish are not the most abundant sunfish species of pristine habitats except in extreme upper reaches of streams typical of creek chubs, green frogs and the like. The greensunfish become more abundant down stream if the habitat is disturbed. Increased green sunfish abundance relative to other sunfishes in breeding colonies increases the likelihood "barnyard follies" will involve green sunfish. Green sunfish are usually pretty easy to cross with other sunfishes which may in part be also be do to the what appears to me to be a rather generalized courtship pattern that may not be an affective hybridization barrier when typical microhabitat differences in nest site are less followed. Also disturbed habitats not always best for communication (visual / olfaction).

As for cuckholders, most I have seen are preety good at targeting their own species. Besides what benefits would there be to hybridizing purposely.

Greens seem to take advantage of everything they can to get ahead. They eat just about anything edible in large quantities so they can grow fast. They live in any habitat they can, so they have a place to live. I think that male greens spawn with any female sunfish they can get onto their nest, just so they can spawn.

That is why greens are so easy to keep. You can train just about any age green sunfish to eat "crap" pellets within days. I mean by that, food that is junk for its content, usually cheap goldfish or koi food full of wheat and corn products. Greens are also fun to keep since they quickly learn you are the food source and will amuse you to gain food.

You can find greens living in just about any kind of habitat. It seems they prefer rocky shorelines in lake/ponds, and small upstream areas, where there are rocks. Yet they still turn up in swampy areas around leaves and sticks. Interestingly, they seem to take on different looks for the different habitats.

In aquariums or small ponds, male greens aggresivly drive females sunfish of any specie onto their nest. If they do not reciprocate with eggs, or sometimes after they do, they are rended of fins and scales. Luckily in the wild, the females can escape before or after.

Once however, the tables were turned by a female green. She seemed not to like the nest provided, and kept going a bit deeper a foot away from the nest. While they spawned the male at the same time tried to fan the new nest. Very interesting indeed!

I suspect that they are closest to the parent species from which all other sunfish species are derived. They are probably closer genetically other sunfish species, than other sunfish species are to each other. Just speculation. Does anybody know if there is any research on this matter?

The phylogenies I've seen clump greens with warmouth and bantams, but disagree on the position of that cluster within Lepomis. As far as actual genetic closeness, I have no clue.