They are superficially similar to reptiles but, along with mammals and birds, reptiles are amniotes and no longer require water bodies in which to breed.

Eventually, their bony fins would evolve into limbs and they would become the ancestors to all tetrapods, including modern amphibians, reptiles, birds, and mammals.

The amphibian brain is less well developed than that of reptiles, birds and mammals but is similar in morphology and function to that of a fish.

In feeding trials, fish, frogs, reptiles, birds and mammals were all found to be susceptible.

Amphibians, reptiles, and birds use the same orifice for excreting liquid and solid wastes, and for copulation and egg-laying ; this orifice is known as the cloaca.

The area contains fossil remains of ancient mammals, birds and reptiles of Oligocene and Miocene age.

The 100 km2 ( 39 sq mi ) area contains fossil remains of ancient mammals, birds and reptiles of Oligocene and Miocene age.

There is evidence that this part of the brain is involved in spatial memory and navigation in fishes, birds, reptiles, and mammals.

Taxonomically, the phylum includes the subphyla Vertebrata, including mammals ( and thus humans ), fish, amphibians, reptiles, birds ; Tunicata, including salps and sea squirts ; and Cephalochordata, comprising the lancelets.

Cape Verde is a group of arid Atlantic islands which are home to a number of birds and reptiles and constitute a unique ecoregion in the World Wildlife Fund classification.

Almost all of the natural environment has been destroyed by conversion to agriculture and logging for firewood, as well as natural soil erosion, all of which has threatened several species of birds and reptiles.

Wildlife diversity is very high ; there are 441 species of amphibians and reptiles, 838 species of birds, 232 species of mammals and 181 species of fresh water fish.

Costa Rica has high levels of endemism ; 81 species of amphibians and reptiles, 17 species of birds and 7 species of mammals are endemic to the country.

According to the World Conservation Monitoring Centre, 209 species of birds, mammals, reptiles, amphibians and plants are endangered.

Early in the Cenozoic, following the K-Pg event, the planet was dominated by relatively small fauna, including small mammals, birds, reptiles, and amphibians.

From a geological perspective, it did not take long for mammals and birds to greatly diversify in the absence of the large reptiles that had dominated during the Mesozoic.

They eat a wide range of material ; in addition to the normal prey of small rodents, reptiles, other amphibians, birds and a range of invertebrates, they also eat plants, dog food and household refuse.

Conversely beetles are prey of various invertebrates and vertebrates including insects, fish, reptiles, birds and mammals.

Although they claimed to be wise, they became fools and exchanged the glory of the immortal God for images made to look like mortal man and birds and animals and reptiles.

There are no endemic species of plants, birds, amphibians, reptiles, mollusks, crustaceans, or mammals on Diego Garcia or in the surrounding waters.

The diet of foxes is largely made up of invertebrates and small mammals, reptiles ( such as snakes ), amphibians, scorpions, grasses, berries, fruit, fish, birds, eggs, dung beetles, insects and all other kinds of small animals.

The large number of extinctions span numerous families of plants and animals including mammals, birds, amphibians, reptiles and arthropods.

In other words all animals except those in the chordate subphylum Vertebrata ( fish, amphibians, reptiles, birds, and mammals ) are regarded as invertebrates.

Their long legs and curved canine teeth are adapted for hunting small mammals, birds, and reptiles, and their large feet and fused leg bones give them a physique well-suited for long-distance running, capable of maintaining speeds of for extended periods of time.

Wagler went so far as to classify Pterodactylus, along with other aquatic vertebrates ( namely plesiosaurs, ichthyosaurs, and monotremes ), in the class Gryphi, between birds and mammals.

In birds, monotremes, and some reptiles, it is the homologous part of the oviduct and leads from the shell gland to the cloaca.

In birds, crocodilians, and monotremes, the ducts are simply extended, together forming an elongated, more or less straight, tube.

In reptiles, birds, and monotremes, the main part of the oviduct is a muscular tube, capable of considerable distension to transport the large eggs that are produced.

The corpus callosum is found only in placental mammals ( the eutherians ), while it is absent in monotremes and marsupials, as well as other vertebrates such as birds, reptiles, amphibians and fish ( other groups do have other brain structures that allow for communication between the two hemispheres, such as the anterior commissure, which serves as the primary mode of interhemispheric communication in marsupials, and which carries all the commissural fibers arising from the neocortex ( also known as the neopallium ), whereas in placental mammals the anterior commissure carries only some of these fibers ).

In most birds, reptiles, insects, molluscs, fish, and monotremes, an egg ( Latin, ovum ) is the zygote, resulting from fertilization of the ovum, which is expelled from the body and permitted to develop outside the body until the developing embryo can survive on its own.

All amphibians, birds, reptiles, and monotremes possess this orifice, from which they excrete both urine and feces, unlike placental mammals, which possess two or three separate orifices for evacuation.

Australia was characterized by marsupials, monotremes, crocodilians, testudines and monitors and numerous large flightless birds.

Discoidal cleavage is commonly found in monotremes, birds, reptiles, and fish that have telolecithal egg cells ( egg cells with the yolk concentrated at one end ).

* Oviparous organisms, including most insects and reptiles, monotremes, dinosaurs and all birds lay eggs that continue to develop after being laid, and hatch later.

This is the reproductive method of most fish, amphibians, reptiles, all birds, the monotremes, and most insects, some molluscs and arachnids.

It is present in most birds and reptiles, and similar structures exist in monotremes, Eleutherodactyl frogs, and spiders.

The Ostrich is the largest living species of bird and lays the largest egg of any living bird ( extinct elephant birds of Madagascar and the giant moa of New Zealand did lay larger eggs ).

Penguin eggs are smaller than any other bird species when compared proportionally to the weight of the parent birds ; at, the Little Penguin egg is 4. 7 % of its mothers ' weight, and the Emperor Penguin egg is 2. 3 %.

This was supported by the description of an additional pterosaur egg belonging to the genus Darwinopterus, described in 2011, which also had a leathery shell and, also like modern reptiles but unlike birds, was fairly small compared to the size of the mother.

In 1866, Haeckel demonstrated that vertebrates could be divided based on their reproductive strategies, and that reptiles, birds and mammals were united by the amniotic egg.

As formulated in Bateman's principle, females have a greater initial investment in producing offspring ( pregnancy in mammals or the production of the egg in birds and reptiles ), and this difference in initial investment creates differences in variance in expected reproductive success and bootstraps the sexual selection processes.

The beaks of many baby birds have a projection called an egg tooth, which facilitates their exit from the amniotic egg.

For there could not have been a first egg to give a beginning to birds, or there should have been a first bird which gave a beginning to eggs ; for a bird comes from an egg.

Hence, in this light, both the chicken and the structure of its egg evolved simultaneously from birds that, while not of the same exact species, gradually became more and more like present-day chickens over time.

In the late 19th and early 20th centuries, the main threats to Osprey populations were egg collectors and hunting of the adults along with other birds of prey, but Osprey populations declined drastically in many areas in the 1950s and 1960s ; this appeared to be in part due to the toxic effects of insecticides such as DDT on reproduction.

One of the better known impacts of DDT is to reduce the thickness of the egg shells on predatory birds.

It has been suggested that the increasing thickness of avian eggshells in proportion to egg mass with increasing egg size places an upper limit on the size of birds.

In amniotes-reptiles, birds, and mammals-the egg is enclosed with an outer layer, or amnion, which has led to further development of the oviduct.

Female birds are reported to destroy the nest on loss of an egg.

Extra-pair copulation with neighbouring birds has been recorded and may be a reason for adult males to stay close to the female before and during the egg laying period.

Before egg laying, both birds will either destroy the large stick nest or add new sticks and leaf lining to an old nest.

Secretary birds lay two to three oval, pale-green eggs over the course of two to three days, although the third egg is most often unfertilised.

As with many birds in the pheasant family, the male takes no part in the incubation of the egg or rearing of the precocial young.

The egg is large compared to that of other birds, weighing 6 – 24 % of the female's weight.

This implies that Deinonychus used body heat transfer as a mechanism for egg incubation, and indicates an endothermy similar to modern birds.

It is a prime location for viewing birds and bird migrations, diamondback turtle egg-laying and horseshoe crab mating and egg laying.