This lifeform is found widely in Eurasia.
Smew (Mergus albellus) is found in the northern forests of Eurasia. While generally wintering on large bodies of freshwater, it occasionally winters in salt water bays to the south. The bold white coloration and black design help identify the male of this beautiful species. This medium-sized duck is typically about sixteen inches long.
Mergansers (Tribe Merginae) are a group of narrow-billed fish-eating ducks. Six species are assigned to this family as
follows: Mergus albellus Smew Eurasia
Mergus australis Auckland EXTINCT Auckland Isles
Mergus cucullatus Hooded N. America
Mergus octosetaceus Brazilian S. America
Mergus serrator Red Breast Holarctic
Mergus squamatus Chinese Orient
Duck and Geese Family (Family Anatidae) contains the familiar ducks and geese. There are about one hundred and fifty-three species in this family.
Some forms are sometimes regarded as species, and at other times are regarded as subspecies. An attempt has been made here to include as species those forms that frequently appear both ways (Anas crecca/carolinensis, for example).
It is also difficult to exactly count the species, as some authors ignore recently extinct species, and other authors include them in their counts. The following recent extinctions have also been included in the lists that follow as these may cause problems for the taxonomist trying to tie out exact counts:
Labrador Duck Camptorhynchus labradorius
Korean Shelduck Tadorna cristata
Madagascan White-Eye Aythya innotata
Auckland Merganser Mergus australis
Pink Headed Duck Rhodonessa caryophyllaca
This family is usually divided into several tribes as it helps the taxonomist and student alike in learning the many species. There is no agreement upon the natural subdivisions of this family. The following divisions were arbitrarily chosen and placed into alphabetical order:
Surface Ducks Anatinae 80 species
Geese and Swans Anserinae 33 species
Diving Ducks Aythyinae 25 species
Mergansers Mergini 6 species
Ruddy Ducks Oxyurinae 9 species
Total 153 species
Waterfowl Order (Order Anseriformes) contains two different
families of rather divergent appearance and habitat. The South American (Neotropical) Screamers contain three species, and the worldwide ducks and geese contain about 153 species to total about 156 species in the order. Actually, at least five of these species are recently extinct, so there are less than the above numbers remaining.
Aves contains about 8,650 different species of living birds known to science. Each year about one new species is discovered in some remote rain forest or remote island. In addition, scientists have been raising many subspecies to full species status which may raise the species count to 10,000.
However, each year about one species goes extinct. The rate of extinction is increasing, and the rate of new discovery is decreasing, so that the number of bird species will soon begin to decline rapidly. Although different taxonomists would organize the birds differently, there are approximately twenty-seven orders of birds. These orders are broken down into about one hundred and fifty-five different families.
Recent research of the genetic structure of some of the shore birds and owls would indicate that the present organization of orders and families should have some modification.
The birds are a worldwide group of animals that are characterized by having the front limbs modified into wings that are used for flying. Perhaps the most unique feature of the birds is the feathers. These feathers are made up of a central support called a quill and a series of small filaments that are hooked together as barbs.
For many years it was believed that Archaeopteryx discovered in Bavaria was the oldest bird from about 150 million years ago. However, in l986, Sankar Chattterjee, a Texas paleontologist, reportedly discovered a bird in the genus Protoavis that lived about 225 million years ago.
Backboned Animals (Phylum Chordata) are the most advanced group of animals on earth. These animals are characterized by having a spinal cord or backbone. Most members have a clearly defined brain that controls the organism through a spinal cord. Fish, amphibians, reptiles, birds, and mammals are in this phylum.
Currently, some taxonomists believe that the fish should be divided into two groups (sharks and regular fishes) and that there are some other primitive groups in the phylum such as hagfish or lampreys.
Animal Kingdom contains numerous organisms that feed on other animals or plants. Included in the animal kingdom are the lower marine invertebrates such as sponges and corals, the jointed legged animals such as insects and spiders, and the backboned animals such as fish, amphibians, reptiles, birds, and mammals.