4
$\begingroup$

I am writing a science-fantasy book series for adolescents (or people aged from 10 to 24 years old if you want) about a weird creature called Céleste Bizarre. One of their friends is an anthropomorphic human-sized flightless falcon called Félicie Faucon (the names sound French because this is my native language). But, I wonder how could a falcon species evolve to be flightless. I mean there is a species called the peregrine falcon that wins the Guinness World Record of the fastest flying animal (and the fastest animal overall). I also know that falcons belong to the Falconiformes order, and their closest relatives are seriamas, parrots, and passerines (Cariamiformes, Pstittaciformes, and Passeriformes, respectively). Together, they form the Australaves grand-order, and the only living flightless Australaves (Telluraves?) species is the kakapo. However, there was once a flightless Falconiformes species: the Jamaican caracara (Caracara tellustris).

$\endgroup$
2
15
$\begingroup$

The big point to consider is why flightlessness evolves. Flight requires an absolutely ridiculous amount of energy, so if there's a way to do without it easily then boom, flightlessness. This usually happens on islands, for reasons I'll get to shortly. Flock of birds gets blown to an island, where there are no predators. They can't get back because they got blown way off course, but there's plenty of (ground-accessible) food and no predators/competition. Importantly, because it is an island, it will stay isolated. That is why New Zealand, pre-colonization, was absolutely dripping with flightless birds (including the kakapo). Same thing on Mauritius, with the Dodo, &c.

Long story short, have a few falcons end up on an island with lots of easy ground-based food sources, and give them a million years or so without outside interference. Or posit an undiscovered island where this has been happening over the past million years; I'm not to optimistic about humans still kicking about a million years from today.

$\endgroup$
2
  • 2
    $\begingroup$ "Falcons isolated on an island" is not very plausible. They already inhabit every continent except Antarctica, and some species migrate thousands of miles each year (e.g. from nesting in the artic tundra to south America in winter). Also their food source relies almost entirely on other flying birds, so they would have to learn to feed on something different within a very short time to survive at all. $\endgroup$
    – alephzero
    Dec 29 '20 at 18:58
  • 1
    $\begingroup$ They don’t strictly need to be isolated. If the island is large enough, and there are no other predators, a resident population may form. Once there’s a resident population, they may find flight isn’t necessary. $\endgroup$
    – Globin347
    Oct 18 at 0:47

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.