Flyers (All Tomorrows)

The Flyers were a posthuman species created by the Qu from a colony of the Star People. They were the most efficient of many flying human species existing accross many Qu-inhabited worlds. Flyers from another world included the ancestors of the Hand Flappers.

These flyers were less derived than other flying posthumans, resembling pterosaur-winged monkeys. Their advantage was a specially designed starshaped heart that funneled oxygen from the lungs to the bloodstream more efficiently.

Flyer (All Tomorrows)

  The specialized heart not only allowed them to fill the skies of their      world with dozens of species but also gave one of the species the          ability to evolve a big brain without losing their ability to fly,                evolving into the Pterosapiens. Other species of flyers eventually lost    their flying ability, but managed to outcompete other animals due to      their supercharged hearts and evolved ground-dwelling and                    swimming species of stupendous size and agility.

Source: WikiFandom