An overview of the class Reptilia
By: M E Skeel
Reptiles evolved from early amphibians and rose to dominate the world for hundreds of millions of years. The dinosaurs became extinct at the end of the Cretaceous period but they live on in a sense through the birds. Mammals are also the descendants of one...
An overview of the class Amphibia or Amphibians
By: M E Skeel
Amphibians are important in an evolutionary sense because early amphibians were the ancestors of all reptiles, birds and mammals. They left the water in the Devonian period about 270 million years ago to become the first vertebrates to colonise land. Their dominance was brief, because...
Characteristics of caecilians
By: M E Skeel
Caecilians look like worms or snakes but they are neither. They are more closely related to frogs and salamanders and are classified as amphibians. They do not resemble other amphibians because they have adapted to a burrowing life style, which has led to the loss...
By: Shekinah Quinnett-Cook
On every continent, except Antarctica, you will find a variety of butterflies in their fragile beauty gracefully flitting from flower to flower, pollinating along the way. There are approximately 20,000 known species of butterflies in the world. In the majority of the United States...
Native birds of Africa: Mousebirds
By: M E Skeel
The mousebirds are a small family of birds, the Coliidae (order Coliiformes), that live exclusively in Africa. They are brown or grey in color but have long tails and conspicuous crests. Their feathers are thick, soft and almost fur-like, due to prominent after-shafts that make...
Native birds of Australia: Mallee and scrub fowl
By: M E Skeel
Australia has a three birds belonging to the family called the Megapodidae (meaning big feet): the Brush turkey, the orange-footed scrubfowl and the malleefowl. These birds are classified in the order Galliformes, which also contains turkeys and chickens, and Megapodes are indeed, heavy, chicken-like birds...
An overview: Birds of prey or raptors
By: M E Skeel
The word raptor is descriptive rather than taxonomic. Raptors are birds with talons instead of claws and large, sharp beaks capable of holding and tearing prey. The other term, bird of prey, is also basically descriptive because this term encompasses two orders of birds and...
A comparison of three similar phyla: platyhelminthes, nematoda, and annelida
By: M E Skeel
A worm is a worm is a worm. Or maybe not. In fact there are many different types of worms and sometimes the only thing they have in common is that vermiform shape. This is particularly true of platyhelminthes (flatworms), nematodes (round worms) and annelids...
A comparison of phylum echinodermata and phylum chordata
By: M E Skeel
Echinoderms are starfish, brittle stars, sea cucumbers and sea urchins. Chordates are fish and birds, reptiles, amphibians and mammals. What is there to compare? What do they have in common? Surprisingly, echinoderms may in fact be the chordates' closest invertebrate relatives. Although superficially very different...
An overview: Salamanders (order Caudata)
By: M E Skeel
Salamanders are amphibians. They are lizard-like in shape, with long bodies and tails, and four legs that stick out to the sides of the body. Unlike lizards, they have soft, scale-less skin and soft shelled eggs that must be laid in water. Salamanders hatch as...

 

1 68 69 70 71 72 99