Order Aptergyidae (kiwis), Casuariidae (cassowaries), Dromaiidae (emus), Rheidae (rheas), and Struthionidae (ostriches). The singular extinct family is Dinornithidae (moas), although there are several extinct species within the extant families. The majority of birds within this order are very large, like ostriches (Struthio camelus), which are the largest extant bird species. Ostriches have a wide geographical range, spanning across Australia, South America, and northern Africa. A notable member of the order is Casuarius casuarius, or southern cassowary, which is a highly aggressive, large bird found in New Guinea and Australia. This species is distinguishable by its featherless head, bright blue skin, and two bright red pendulous wattles that hang from the neck. (Beehler, et al., 2016; "Dinornithidae", 2022; Fuller, 1987; Marchant and Higgins, 1990)includes all of the flightless birds, also known as ratites due to their raft-like sternum that lacks a keel. The order is comprised of five extant families and one extinct family. The five families are
Rheidae), the Northwestern portion of the Ethiopean Region (Struthionidae), the southeastern region of the Palearctic region (Struthionidae), and the Australian region (Apterygidae, Cassuariidae, Dromaiidae, a small introduced population of Struthionidae, and extinct Dinornthidae). No members of are found in the Nearctic nor Oriental regions. (Beehler, et al., 2016; Bellis, et al., 2004; Marchant and Higgins, 1990; Ryeland, et al., 2021; Taborsky and Taborsky, 1995; Worthy, 2017)have a wide geographical range, covering most of the Southern hemisphere and a small region within the Northern hemisphere. They are found in the southwestern portion of the Neotropical region (
Casuariidae and Apterygidae. Rheiidea and Struthionidae are found in grasslands and savannahs. The extinct family Dinornithidae was believed to have inhabited the marshlands, grasslands, and forests of New Zealand. Dromiaidae occupies almost every habitat in Australia, avoiding urban areas and desert regions during the dry seasons, though they can be found there when it rains. Most avoid areas of high urban settlement, but will often be found in areas of agricultural development and roadways. Members of family Casuariidae often have dangerous interactions with humans due to habitat disruption. (Beehler, et al., 2016; Bellis, et al., 2004; Kofron, 1999; Marchant and Higgins, 1990; Taborsky and Taborsky, 1995; Worthy, 2017)inhabit various habitats. Many reside in dense, tropical rainforests, such as families
Aves and subclass Paleognathae. have a complex taxonomic history. In the past, species were often placed into their own order, which resulted in many different orders for the individual bird species. There is some debate over the classification of , as some researchers place order Tinamiformes (subclass Paleognathae), in . In general, has a very complicated history and is still heavily debated today. (Beehler, et al., 2016; Bradford and Westcott, 2010; Cramp, et al., 1977; Fuller, 1987; "IUCN Red List of Threatened Species", 2021; Marchant and Higgins, 1990)are in class
Struthio camelus) males have black or dark brown feathers with striking white plumage at the ends of their wings, tail feathers, and around their necks, which are used for mating displays and hostile encounters. Cassowaries (Casuarius) have very distinct coloration, with the three different species having bright coloration on the skin of their neck and a characteristic casque on the top of their head. Northern cassowaries (Casuarius unappendiculatus) have bright blue coloration on their necks and heads, with a red waddle on the base of their necks, much like southern cassowaries (Casuarius casuarius) and dwarf cassowaries (Casuarius bennetti). Unlike its relatives, northern cassowaries (Casuarius unappendiculatus) also feature a bright yellow patch on their necks, adding a beautiful contrast between the red of their waddles and the blue bases of their necks. (Beehler, et al., 2016; Cramp, et al., 1977; Marchant and Higgins, 1990; Olson and Turvey, 2013)are grouped together based on their sternum that lacks a keel, which is a projection of bone found on the sternum of flying birds that provides a space for flight muscles. The raft-like sternum of gives them the name “ratites," which is a name commonly used for this order. All the birds in the order are flightless and feature long legs that benefit their ground-dwelling behavior. All birds also have brown or black feathers, with a few families having distinct coloration. Ostrich (
Apteryx) have been observed to have monogamous breeding pairs. In most groups, the nests are primarily protected by the males while the females go find more mates. All members of have been observed to have solitary nests, even those that are social species, such as emus (Dromaius). (Beehler, et al., 2016; Cramp, et al., 1977; Fuller, 1987; Marchant and Higgins, 1990)typically have multiple mates during a single mating season. Out of all of the groups found within the order, only kiwis (
Apterygidae), cassowaries (Casuariidae), and ostriches (Struthionidae) having clutches of around three to six eggs, to large, with rheas (Rheidae) having clutch sizes that have been reported to be in the thirties. Gestation periods for typically last around a month to two months. Because this order contains flightless birds, young are able to move around on their own within a day or two. Juveniles will typically remain with the parent(s) for several months, and will often remain in the area until adulthood. (Beehler, et al., 2016; Cholewiak, 2003; Cramp, et al., 1977; Fuller, 1987; Marchant and Higgins, 1990)' breeding seasons range throughout the entire year, with the majority of species falling between the months of June through October. Clutch sizes range from small, with kiwis (
Struthionidae) and two species of kiwi (Apteryx haastii and Apteryx australis), males and females will both incubate the eggs. Males and females will also care for the offspring. Juvenile are able to move around shortly after hatching, due to being a flightless species. Young will stay with their parents for several months, often remaining in the area until adulthood. (Beehler, et al., 2016; Cholewiak, 2003; Cramp, et al., 1977; Marchant and Higgins, 1990)males typically invest more into the offspring than the females. Females will often lay the eggs and incubate them for a week or two, then the males will take over incubation full-time and raise the offspring. During the incubation period, males will consume very little food and water. With ostriches (
Casuariidae), emus (Dromaiidae), and kiwis (Apterygidae) are solitary species, with kiwis only interacting with conspecifics while breeding in monogamous pairs during the breeding season. Ostriches (Struthionidae) and rheas (Rheidae) can live in groups, but can also be solitary. Most ostriches live in small family groups or harems. Rheas will form social groups during breeding season, usually returning to a solitary life when the season ends. (Beehler, et al., 2016; Cramp, et al., 1977; Fuller, 1987; Marchant and Higgins, 1990)have mostly solitary species. Cassowaries (
Casuarius casuarius). Southern cassowaries have very sharp claws on their incredibly thick legs, which they use to violently kick at threats. This bird is often said to be very aggressive, causing many issues with local humans. They are also one of the few birds to have killed a person by directly attacking them. Although these birds have killed several hundred people, most attacks were due to territory issues and food, as people will occasionally feed the wildlife thus causing the cassowaries to associate humans with food. (Beehler, et al., 2016; Cramp, et al., 1977; Fuller, 1987; Hodges, 2018; Kofron, 1999; Marchant and Higgins, 1990; Naish, 2018)' behaviors vary between species. Many of the larger species will act very aggressive towards conspecifics, other species, and humans. Almost all but kiwis will show aggression towards humans. The most notorious are southern cassowaries (
C. casuarius), have been known to scavenge carcasses. are very important for seed distribution, especially those that reside in dense, forest environments. The passage of fruits and seeds through the digestive tract of these birds has been shown to have a very important role in the germination of forests. Several papers have been published on southern cassowaries and their importance to the rainforests of northern Australia and New Guinea. (Beehler, et al., 2016; Bradford and Westcott, 2010; Cramp, et al., 1977; Fuller, 1987; Hodges, 2018; Marchant and Higgins, 1990)eat a wide range of food, including fruits, insects, worms, vegetation, and seeds. Some species, like southern cassowaries (
Panthera leo) and dingos (Canis lupus dingo) prey on the birds - although in many cases, are poor targets due to their strong defenses. Their eggs and young are a much easier target. The most dangerous predator for is probably humans. Humans have been hunting for thousands of years and are responsible for driving moas (Dinornithidae) extinct. Every species that was driven extinct in Struthiuoniformes was the result of anthropogenic impacts. (Beehler, et al., 2016; Cramp, et al., 1977; Fuller, 1987; Marchant and Higgins, 1990)are well-equipped to deal with predation. These birds are built for speed and defense, with all but kiwis being over five feet tall. have long legs designed for running. These legs feature very sharp claws on the toes, which are often combined with a very powerful kick to act as an anti-predator defense mechanism. Because are found all over the world, they have a variety of predators. Most commonly, large cat and dog species such as lions (
(Beehler, et al., 2016; Bradford and Westcott, 2010; Cramp, et al., 1977; "Dinornithidae", 2022; Fuller, 1987; "Greater Rhea", 2016; "IUCN Red List of Threatened Species", 2021; "Lesser Rhea", 2018; Marchant and Higgins, 1990; "North African Ostrich Recovery Project", 2020; "Our Work With Kiwi: New Zealand Native Land Birds", 2018; Worthy, 2017)' populations are on the decline. Their main threats are habitat loss and deforestation, especially for kiwis and cassowaries, both of which have relatively small ranges that are easily disrupted by human activity. Although are declining and are at risk for becoming endangered, there is conservation action being taken around the world. New Zealand's government is working to protect the kiwis and educate their citizens on the importance of kiwis. Additionally, zoos around the world are working towards conservation efforts for , as well as working on restoring the native ranges of and protecting their habitats from destruction.
Ellie Bollich (author), Colorado State University, Sydney Collins (editor), Colorado State University.
Living in Australia, New Zealand, Tasmania, New Guinea and associated islands.
living in sub-Saharan Africa (south of 30 degrees north) and Madagascar.
living in the southern part of the New World. In other words, Central and South America.
living in the northern part of the Old World. In otherwords, Europe and Asia and northern Africa.
uses sound to communicate
living in landscapes dominated by human agriculture.
having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.
an animal that mainly eats meat
either directly causes, or indirectly transmits, a disease to a domestic animal
Found in coastal areas between 30 and 40 degrees latitude, in areas with a Mediterranean climate. Vegetation is dominated by stands of dense, spiny shrubs with tough (hard or waxy) evergreen leaves. May be maintained by periodic fire. In South America it includes the scrub ecotone between forest and paramo.
uses smells or other chemicals to communicate
used loosely to describe any group of organisms living together or in close proximity to each other - for example nesting shorebirds that live in large colonies. More specifically refers to a group of organisms in which members act as specialized subunits (a continuous, modular society) - as in clonal organisms.
helpers provide assistance in raising young that are not their own
in deserts low (less than 30 cm per year) and unpredictable rainfall results in landscapes dominated by plants and animals adapted to aridity. Vegetation is typically sparse, though spectacular blooms may occur following rain. Deserts can be cold or warm and daily temperates typically fluctuate. In dune areas vegetation is also sparse and conditions are dry. This is because sand does not hold water well so little is available to plants. In dunes near seas and oceans this is compounded by the influence of salt in the air and soil. Salt limits the ability of plants to take up water through their roots.
ranking system or pecking order among members of a long-term social group, where dominance status affects access to resources or mates
a substance used for the diagnosis, cure, mitigation, treatment, or prevention of disease
humans benefit economically by promoting tourism that focuses on the appreciation of natural areas or animals. Ecotourism implies that there are existing programs that profit from the appreciation of natural areas or animals.
animals that use metabolically generated heat to regulate body temperature independently of ambient temperature. Endothermy is a synapomorphy of the Mammalia, although it may have arisen in a (now extinct) synapsid ancestor; the fossil record does not distinguish these possibilities. Convergent in birds.
union of egg and spermatozoan
an animal that mainly eats leaves.
A substance that provides both nutrients and energy to a living thing.
forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.
an animal that mainly eats fruit
an animal that mainly eats seeds
An animal that eats mainly plants or parts of plants.
An animal that eats mainly insects or spiders.
fertilization takes place within the female's body
referring to animal species that have been transported to and established populations in regions outside of their natural range, usually through human action.
animals that live only on an island or set of islands.
offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).
parental care is carried out by males
marshes are wetland areas often dominated by grasses and reeds.
makes seasonal movements between breeding and wintering grounds
Having one mate at a time.
having the capacity to move from one place to another.
This terrestrial biome includes summits of high mountains, either without vegetation or covered by low, tundra-like vegetation.
the area in which the animal is naturally found, the region in which it is endemic.
active during the night
generally wanders from place to place, usually within a well-defined range.
an animal that mainly eats all kinds of things, including plants and animals
reproduction in which eggs are released by the female; development of offspring occurs outside the mother's body.
the business of buying and selling animals for people to keep in their homes as pets.
Referring to a mating system in which a female mates with several males during one breeding season (compare polygynous).
the kind of polygamy in which a female pairs with several males, each of which also pairs with several different females.
having more than one female as a mate at one time
rainforests, both temperate and tropical, are dominated by trees often forming a closed canopy with little light reaching the ground. Epiphytes and climbing plants are also abundant. Precipitation is typically not limiting, but may be somewhat seasonal.
Referring to something living or located adjacent to a waterbody (usually, but not always, a river or stream).
an animal that mainly eats dead animals
scrub forests develop in areas that experience dry seasons.
breeding is confined to a particular season
remains in the same area
reproduction that includes combining the genetic contribution of two individuals, a male and a female
one of the sexes (usually males) has special physical structures used in courting the other sex or fighting the same sex. For example: antlers, elongated tails, special spurs.
associates with others of its species; forms social groups.
a wetland area that may be permanently or intermittently covered in water, often dominated by woody vegetation.
uses touch to communicate
that region of the Earth between 23.5 degrees North and 60 degrees North (between the Tropic of Cancer and the Arctic Circle) and between 23.5 degrees South and 60 degrees South (between the Tropic of Capricorn and the Antarctic Circle).
Living on the ground.
defends an area within the home range, occupied by a single animals or group of animals of the same species and held through overt defense, display, or advertisement
the region of the earth that surrounds the equator, from 23.5 degrees north to 23.5 degrees south.
A terrestrial biome. Savannas are grasslands with scattered individual trees that do not form a closed canopy. Extensive savannas are found in parts of subtropical and tropical Africa and South America, and in Australia.
A grassland with scattered trees or scattered clumps of trees, a type of community intermediate between grassland and forest. See also Tropical savanna and grassland biome.
A terrestrial biome found in temperate latitudes (>23.5° N or S latitude). Vegetation is made up mostly of grasses, the height and species diversity of which depend largely on the amount of moisture available. Fire and grazing are important in the long-term maintenance of grasslands.
uses sight to communicate
young are relatively well-developed when born
2022. "Dinornithidae" (On-line). Animal Diversity Web. Accessed February 12, 2022 at https://animaldiversity.org/accounts/Dinornithidae/classification/#Dinornithidae.
2016. "Greater Rhea" (On-line). IUCN Redlist. Accessed February 13, 2022 at https://www.iucnredlist.org/species/22678073/92754472.
2021. "IUCN Red List of Threatened Species" (On-line). Accessed April 25, 2022 at https://www.iucnredlist.org/search?taxonomies=22672859&searchType=species.
2022. "Keel" (On-line). Oxford Reference. Accessed March 23, 2022 at https://www.oxfordreference.com/view/10.1093/oi/authority.20110810105209696.
2018. "Lesser Rhea" (On-line). IUCN Redlist. Accessed February 13, 2022 at https://www.iucnredlist.org/species/22728199/132179491.
2020. "North African Ostrich Recovery Project" (On-line). Accessed April 25, 2022 at https://saharaconservation.org/north-african-ostrich/.
2018. "Our Work With Kiwi: New Zealand Native Land Birds" (On-line). Accessed April 25, 2022 at https://www.doc.govt.nz/nature/native-animals/birds/birds-a-z/kiwi/docs-work/.
Beehler, B., T. Pratt, M. LeCroy. 2016. Birds of New Guinea: Distribution, Taxonomy, and Systematics. United Kingdom: Princeton University press.
Bellis, L., M. Martella, J. Navarro, P. Vignolo. 2004. Home range of greater and lesser rhea in Argentina : relevance to conservation. Biodiversity and Conservation, Volume 13: 2589-2598.
Bradford, M., D. Westcott. 2010. Consequences of southern cassowary (Casuarius casuarius, L.) gut passage and deposition pattern on the germination of rainforest seeds. Austral Ecology, Volume 35, Issue 3: 325-333.
Cholewiak, D. 2003. "Rheidae" (On-line). Animal Diversity Web. Accessed March 23, 2022 at https://animaldiversity.org/accounts/Rheidae/.
Cooper, R., K. Mahrose, J. Horbanczuk, R. Villeguz-Vizcaino, S. Kenou Sebei, A. Faki Mohammed. 2009. The wild ostrich (Struthio camelus): a review. Tropical Animal Health and Production, Volume 41: 1669.
Cramp, S., K. Simmons, I. Ferguson-Lees, R. Gillmor, P. Hollom, R. Hudson, E. Nicholson, M. Ogilvie, P. Olney, K. Voous, J. Wattel. 1977. Handbook of the Birds of Europe the Middle East and North Africa. Oxford: Oxford University Press.
Fuller, E. 1987. Extinct Birds. United Kingdom: Comstock Publishing Associates.
Hodges, K. 2018. "Rhea americana" (On-line). Animal Diversity Web. Accessed April 01, 2022 at https://animaldiversity.org/accounts/Rhea_americana/.
Kofron, C. 1999. Attacks to humans and domestic animals by the southern cassowary (Casuarius casuarius johnsonii) in Queensland, Australia. Journal Of Zoology, Volume 249, Issue 4: 375-381. Accessed February 05, 2022 at https://www-webofscience-com.ezproxy2.library.colostate.edu/wos/woscc/full-record/WOS:000084429000001.
Magige, F., E. Roskaft. 2017. "Medicinal and Commercial Uses of Ostrich Products in Tanzania" (On-line). Accessed April 13, 2022 at https://pubmed.ncbi.nlm.nih.gov/28835266/.
Marchant, S., P. Higgins. 1990. Handbook of Australian, New Zealand, and Antarctic Birds, Volume 1. Australia: Oxford University Press.
Naish, D. 2018. "How Dangerous are Cassowaries, Really?" (On-line). Scientific American. Accessed April 01, 2022 at https://blogs.scientificamerican.com/tetrapod-zoology/how-dangerous-are-cassowaries-really/.
Olson, V., S. Turvey. 2013. The evolution of sexual dimorphism in New Zealand giant moa (Dinornis) and other ratites. Proceedings of the Royal Society B, Volume 280, Issue 1760: 20130401.
Ryeland, J., T. Derham, R. Spencer. 2021. Past and future potential range changes in one of the last large vertebrates of the Australian continent, the emu Dromaius novaehollandiae. Scientific Reports, Volume 11: 851.
Taborsky, M., B. Taborsky. 1995. Habitat Use and Selectivity by the Brown Kiwi (Apteryx australis mantelli) in a Patchy Environment. The Auk, Volume 112, Issue 3: 680-689.
Worthy, T. 2017. "Moa - Distribution" (On-line). The Encyclopedia of New Zealand. Accessed February 13, 2022 at https://teara.govt.nz/en/moa/page-2.