Neocene epoch differs from droughty and cool Holocene in significant biological efficiency. The areas of savannas and deserts were reduced and wood and bush areas had extended. In territory of Australia new habitats able to support numerous populations of large animals – thickets of eucalyptuses and perennial graminoids – had appeared. Accordingly, in fauna of this continent appreciable changes had cased: many large animals had evolved. A part of them was descendants of introduced species, and the other part had evolved from native species of continent. Among birds the group of false moas – large flightless descendants of emu – had appeared. They had occupied all Australian-New Guinean continent, and had formed some species adapted to different conditions of inhabiting.
In plain districts overgrown with grass, the savanna false moa, the largest species of this family, lives. Growth of adult bird may reach 350 cm at weight up to 350 kg. This bird differs in rather massive constitution and thick legs. Therefore is not able to run quickly. But due to large growth this bird beforehand notices danger, and life in herd gives advantage of collective defense.
The feathering of savanna false moa is colored sand tone. Feathers are narrow and more similar to wool. They cover all body in regular intervals, but sides of head, throat and forward part of neck of this bird are covered with featherless skin of violet-red color. White coloring of feathers on nape sharply contrasts with it. These feathers are long and also form thin crest which is used for submission of signals and recognition of congeners. At males it is larger, than at females.
At savanna false moa the beak is not specialized to any certain kind of food. It is natural feature: the bird eats practically everything that is possible to be found in savanna. The most part of diet of these species includes elevated parts of grassy plants, but this bird frequently digs out tubers and bulbs by sharp claws. Also savanna false moa willingly pecks insects and small vertebrates, down to young rabbits (this bird can swallow animals of such size entirely). To digest food better, savanna false moas swallow chicken egg-sized stones.
Usually herds of these birds numbering up to 30 - 40 birds wander on savannas, not adhering to the certain territory. As the need for water at birds is less than at mammals, they appear on watering places approximately once in two - three days, using the moisture contained in eaten plants in other time. Due to this feature birds can feed in districts unsuitable for life of local herbivorous animals like camelopes. There is no strict hierarchy in herd of birds, and the competition between males begins mainly during courtship season – shortly before rain season. During courtship season males start to show aggression to each other. They start to drive away each other from females, uttering loud blares and strongly puffing throat.
Savanna false moas are not strict polydins: in various cases one male can form pair family, or nesting group with several females – it depends on number of females in herd. Accordingly, the size of clutch of this species varies from ten up to twenty eggs and more in one nest. The clutch is hatched by both parents (or male and all females of breeding group) alternately. Chicks hatch after 45 days; they are well advanced, covered with down of yellowish color with narrow dark longitudinal strips. They can feed independently from the first day of life. Chicks keep mainly with female, and male protects territory where the hatch is feeding.
At the age of ten days at chicks feathers start to grow. Young birds till the first year of life reach about half of weight of adult bird. At three-year age they start to take part in courtship displays.
False moas have achieved the big success in struggle for existence, that is expressed in variety and prevalence of these birds in Meganesia. Close species of this genus inhabit other biotopes:
Desert false moa (Pseudodinornis desertophilum) lives in droughty areas of south-west of continent. It differs in graceful constitution and ability to live in hot dry climate.
Mountain false moa (Pseudodinornis orophilum) lives in completely other conditions, than the previous species: in mountain woods and bush thickets of Great Dividing Ridge. It is the smallest species in family: adult individuals grow up to 150 cm in height, and weigh about 100 kg. Birds of this species differ in stumpy constitution: neck and legs at them are rather short. Mountain false moas do not differ in run abilities, but they can skip on stones and easily move on abrupt slopes.
Featherless sites of skin on throat are not present, but at males fluffy “beard”, which it shows during courtship displays, develops. Feathering of this bird is rather homogeneous; feathers are narrow, a little similar to wool. To winter feathers become wider, improving thermal protection of birds. Coloring of body is soft, brownish-olive tones; head is lighter than body. Legs are feathered up to middle of hypotarsus, are covered with dark feathers. To winter feathers on legs extend, forming warm “trousers”.
These birds are steadier against a cold, than local mammal, mountain camelopes. They live at the greater height, than these animals, and avoid competition to them due to it. However, to winter mountain false moas of this species go down in valleys. They eat grass and branches of evergreen bushes.
Mountain false moas are monodins; they nest in rich bush, hiding the nest location. In their clutch it is to 5 - 8 large eggs.
Wood false moa (Pseudodinornis sylvaticus) lives in rich tropical woods at the north of Meganesia. This species is medium-sized representative of the genus: it reaches only 2 meters in height, and weighs 150 – 200 kg. Its feathering is colored greyish-green tone with white spots on trunk, imitating light spots on wood litter. Due to such colouring the bird can remain imperceptible, freezing in bushes or near the fallen tree. Besides this bird is able to run quickly, because it is combined rather gracefully, resembling an ostrich by proportions. For recognition of congeners on throat of this bird there is a bright label - the blue area of naked skin bordered by silver-gray feathers. Except for this label, bird is differing in “eyebrows” of lengthened black feathers well distinguished on grey feathering of head. Wood false moa is monodin, and pairs at these species are kept till all life. Male and female build in common nest somewhere in shelter, usually in bush in the fallen site of wood. The nest represents a small hole in the ground without litter. In clutch there are about green-shelled 10 eggs. The incubating lasts about 35 days. Chicks have striped colouring: along back and on sides wide longitudinal brown stripes stretch on yellowish background.
Striped, or jarra false moa (Pseudodinornis jarrae) lives in rarefied eucalyptine woods (this vegetative community is named “jarra”) at coast of gulf of Eyre and at southern coast of continent. As against other species, at jarra false moa it is striped colouring of body of alternating brown and yellow strips, representing a juvenile attribute. Head of bird is black; neck is white with pale longitudinal strips which become brighter on body.
It is one of large species of genus: the adult male reaches 2,5 - 2,8 m in height and weighs about 300 kg. Jarra false moa is rather sluggish bird which keeps in small groups – about 10 – 15 adult birds. It lives in districts overgrown with bush and undersized wood species of eucalyptus (the characteristic Australian vegetative community named “jarra”).
Jarra false moa eats eucalyptus leaves – this kind of forage is not accessible to many herbivores. Leaves of eucalyptus are poisonous enough, and contain a plenty of oils, therefore only the most specialized herbivores can eat them. Due to special enzymes this bird neutralizes and decomposes poisonous substances, and can browse even young sprouts of eucalyptuses. In districts where such birds are fed, eucalyptuses grow as low trees with “pruned” crone.
Jarra false moas are inclined to social life – birds nest together, and nests in colony are placed at the distance of several meters from each other. In clutch there are no more than eight large eggs with shell of brown color. Both parents hatch it, but the posterity is looked after only by the female. Usually chicks keep near mother only the first week of life, and later then unite to “kindergarten”, and females in common look at them. Young birds eat ground vegetation, and start to use for food eucalyptus leaves only from bi-monthly age.