Skink and Anole
This one is a bit oddball, it's in the style of a just-so story, with Bennu in the role of the Trickster-hero, which might confuse non-mytholgy nerds because the Skink and Anole in this aren't just random characters of those species, but the original ones back in the mythological dawn time, the anthropomorphized totems... but this is just a silly 'non canon' thing I thought of at the powwow when I couldn't sleep, not an excuse to examine motifs of Native American mythology.
There are two kinds of lizards common in the southern lands: the anole, that most people call chameleon, that changes from green to brown; and the skink, the fat lizard with stripes on its back. So both are colorful in different ways, and both lose their tails where snakes and turtles do not. This is how it happened:
Many moons ago both were plain lizards, as all lizards were the same then, and there were two females named Anole and Skink that looked alike. Bennu was chasing both of them, as he went about playing with all the creatures in the forest. This was when he was young and full of magic, and he would offer one magical favor in return for one sexual favor, but only one as it was the easiest way to be fair.
He was playing tag with Anole when he grabbed her tail, pulled her to him hand over hand, she laughed and squealed at his amorous advances, and began moaning loudly as he began his business under her tail, wrapping around her and biting her neck lizard style. After a vigorous session they lay entangled, and she said "Oh Bennu, it was not fair how you caught me- there are many predators in the woods looking to eat a small lizard... could you make it so I could escape even if my tail is caught?" After some thinking he decided to make it so her tail would fall off and wiggle about, then grow back. She thought it was kind of gross, but better than being eaten. Soon Skink heard of this and was greatly jealous, and after lengthy oral arguments he did the same for her.
Anole scoffed at the idea she had competition, and seduced Bennu again, hiding naked in the green leaves and calling to him while he hunted for her, and she teased him by showing her bottom, but when he ran to it she was hidden again, until finally he agreed to give her another wish if she would have sex with him. When she climbed out onto a brown branch he pounced on her, rolling her on her back and sliding his belly against her smooth pale scales as he pumped between her legs, pulling out to spurt his seed over her belly to keep her from getting pregnant. Then he made it so she could turn brown as well as green, since those are the two colors most common in the forest. He made her promise not to tell, but soon Skink noticed and thought hard of how to win another favor for herself, and decided on pity. Weeping, she came to him: "So I am not beautiful, only a plain green lizard, that you use once and throw away. What did Anole do to make you break your rule? Why is she more beautiful than me? Could you not make me the beauty you wish I was?" He grudgingly agreed, but only because it roused his artistic interest. He made he scales shiny and smooth instead of rough like Anole, and made her dark colored with bright stripes running along her back, five lines from his five fingers. Indeed, he liked her look so much he desired to enjoy her new look with more than his eyes, and she eagerly agreed, becoming his lover for many days.
Anole heard of this, and pondered what to do, what she needed. She had trouble finding a male, as they were so well hidden and timid. So she came begging to Bennu for one last favor, a way to find a brave strong male to breed with. Again he was reluctant, but saw no way out of it, as he offered protection to his forest dwellers, and she was not trading sex for it. So he pondered some time, and finally he found a male like her, only he was too well hidden. Bennu tried to think of a way to let him stand out, to show off, but also hide, and finally he got mad and grabbed the male's throat and pulled it, stre-e-e-etching it, and when he let go it snapped back into place. He decided this was what he needed, and stre-e-e-etched it out again, and slap-slap-slapped some red paint on it. Then he told Anole to look as the great strong male stood on a branch, bobbing his head and puffing his throat, red flag showing, unafraid of birds or foxes, and Anole ran to him, and he mated with her, and she laid many eggs, the first of the anoles.
Bennu went back to his bed, where Skink was laying naked and waiting. He asked if she was going to want a gift for her children, but she smiled and said she already had one, because her belly was full of eggs he fertilized in their love making. He had been so enamored with his creation he forgot that he should not impregnate her himself, and so the skinks became a different kind of lizard from the anole, and Skink won the contest because all her descendants are the offspring of Bennu.
So that is where the anole and skink come from, and why they are different.