Ornithology

The number of toes a bird has depends on the species. Most birds have four toes on each foot, but some have fewer.

• Anisodactyl: This is the most common arrangement in birds, with three toes pointing forward and one pointing backward. [https://academy.allaboutbirds.org/how-many-toes/]
• Zygodactyl: Two toes point forward and two point backward. This arrangement is common in woodpeckers, owls, and parrots. [https://academy.allaboutbirds.org/how-many-toes/]
• Heterodactyl: Similar to zygodactyl, but only found in trogons. The inner two toes point forward, and the outer two point backward. [https://en.wikipedia.org/wiki/Bird_foot]
• Pamprodactyl: All four toes point forward. This arrangement is found in swifts. [https://en.wikipedia.org/wiki/Bird_foot]
• Some birds, like ostriches, only have two toes. [https://www.sciencefocus.com/nature/why-do-ostriches-have-two-toes/]

Therefore, depending on the species, a bird can have two, four, six, or eight toes.

Yes, there are many birds in the world. It is estimated that there are around 50 billion individual wild birds in the world.

Here are some additional details:

• Species Diversity: There are approximately 10,000 different species of birds inhabiting various ecosystems across the globe.
• Habitat Range: Birds can be found in virtually every type of habitat, from the polar regions to tropical rainforests, and from deserts to oceans.

For more detailed information, you can refer to these sources:

• PNAS Study provides an estimate of the world's bird population.