This is a bird order that contains a large number of birds that may or may not seem to resemble each other.

With the use of molecular biology tools, there currently seems to be six families that make up this order and they are: Rallidae (rails, gallinules, coots, and crakes), Sarothruiridae (flufftails), Heliornithidae (finfoots), Psophiidae (trumpters), Aramidae (limpkin), and Gruidae (cranes).

Of the six families, only three are spotted within the US: Gruidae, Aramidae, and Rallidae.

The family Rallidae is the only one with a worldwide distribution, and includes 138 living species. The family Gruidae (15 different crane species) is absent from South America and Antarctica, and many of the species are listed as endangered. The limpkin is the only member of both the genus Aramus and the family Aramidae, and can be found within the warm wetlands of the Americas (within the US–mainly Florida, and then throughout Central America into South America).

The family Sarothruridae (fifteen species within 3 genera) is found mainly in Madagascar and sub-Saharan Africa. The family Heliornithidae contains three species in three genera (one per each), and can be found in Africa, Central & South America, and eastern India through Southeast Asia.

The family Psophiidae (consists of 3 or 8 species in a single genera) is found only in South America, specifically within Amazon rainforest and the Guiana Shield (the rainforests to the north of the Amazon within Guyana, Suriname, French Guiana, southern Venezuela and the northern part of Brazil, along with a bit of Columbia).

The diets, habitats, and migratory habits of the members that make up this order are as diverse as the families they’re found in. My photography goals for the order include getting at least one picture of a member of each family, and a picture of a species (regardless of family) on each continent.

Reference: https://en.wikipedia.org/wiki/gruiformes