All species of birds belong to the phylum Chordata. Animals in the Chordata phylum share many traits as embryos; however, these traits can disappear by birth, allowing for great diversity in the phylum.Continue Reading
Chordata embryos all contain a notochord, some form of a hollow nerve cord, pharangeal slits and a postanal tail. Mammals, bony and cartilaginous fish, reptiles and amphibians are all considered Chordata.
Birds are distinguishable from other Chordata by the presence of feathers; however, most bird species also have scaly feet, light bones for flying, and particularly good vision. Experts believe birds, rather than reptiles, are the descendants of dinosaurs.Learn more about Birds
While the actual number of bird species is unknown since new species continue to be discovered, there are approximately 10,500 known species of birds in the world, according to the International Ornithologists’ Union. There are approximately 21,000 subspecies of birds.Full Answer >
Nocturnal birds, such as owls and nighthawks, always fly at night, and some other species of birds, such as thrushes, vireos, nuthatches and many sparrows, fly at night during migration periods only. Most species of birds rest during the night.Full Answer >
All species of birds have backbones because birds are vertebrates. The animal kingdom can be organized by grouping classes of organisms together based on key physical characteristics. Whether or not an organism has a backbone or spinal column is one means to classify animals.Full Answer >
Worldwide, scientists estimate that there are approximately 9,000 to 10,000 species of birds and 22,000 subspecies of birds. Each animal kingdom is split into large groups called phyla. Each phylum is split into smaller groups called classes.Full Answer >