Enter the Magical World of the Ratites Quiz

Answer: True

Birds of the class Aves can be split into two groups, Neognathae and Paleognathae. Paleognathae includes all ratites, while Neognathae consists of all other living birds. Molecular clock evidence suggests that this split took place while the dinosaurs were still around, in the early Cretaceous.

However, the first ratite fossils are only found in the late Cretaceous, leading some to argue that the ratites only diversified into a true group after the asteroid that wiped out the dinosaurs, which resulted in a variety of open niches for birds such as the ratites to fill.

Answer: ostrich

Wild ostriches are limited mainly to Africa - the common ostrich can be found across Northern, Eastern, and Southern Africa, while the Somali ostrich is limited to the Horn of Africa. For most of the recent past, however, the Arabian ostrich, a subspecies of the common ostrich, was present in the Middle East, dying out only in the 20th century. Ostriches were also taken to Australia for their meat, and there is a small feral population there, descendants of ostriches which escaped human captivity.

Ostriches do not bury their heads in the sand. They lay their eggs on a nest in the ground, and occasionally poke their head in to take a look, which may be where this myth originates.

Answer: kiwi

The use of the term "kiwi" to refer to New Zealanders dates back to the early 1900s, when it was used for the NZ rugby team. It became popular as a term for any New Zealander after the two World Wars, as NZ soldiers were often referred to as kiwis.

It is thought that kiwis stayed small after losing their ability to fly because there was already a large flightless bird native to New Zealand, who we will meet later in this quiz.

Answer: emu

Emu reproduction is the opposite of what we often see in the animal kingdom - the female courts the male, and attempts to prevent other females from approaching him. Once the egg has been laid, it is the male who does all the work of incubating it, without eating or drinking, while the female often finds another male to create an egg with.

Despite the attempts of the Australian government in the 1920s, emus are still common throughout Australia, especially in the less inhabited parts in the west and inland.

Answer: rhea

Before we understood evolution, it was thought that each animal was created to suit its environment. In South America, however, Darwin encountered both rhea species, which overlapped in habitat but yet were quite different. This led Darwin to the realization that both rhea species were descended from a common ancestor, yet had diverged into two separate birds. Rheas, along with the famous Galapagos finches, ultimately helped him formulate the theory of evolution, which has helped us understand animal speciation and adaptation to a much greater extent.

Answer: cassowary

Cassowaries have an imposing crest on their head, a brightly-colored blue head, and sharp claws on their feet. While ostriches account for more deaths per year, partly due to their larger population and contact with humans, cassowaries have often been called "the world's most dangerous bird". The claws on their feet are deadly and can kill. Like all ratites, they are mainly herbivores, but meat makes up a larger part of their diet than any other ratite.

Cassowaries have often been called "the last dinosaur" or "living dinosaurs". While this is of course not genetically correct, as they are no more related to dinosaurs than any other bird, their striking appearance makes the terms understandable.

Answer: elephant bird

Many of the world's biggest megafauna went extinct in the last 10,000 years, unable to cope with human predation and habitat loss. It is no surprise that most of the world's biggest land animals live in Africa, as their ancestors evolved alongside humans and thus were able to avoid overhunting and extinction.

The first permanent human settlements in Madagascar date only to the mid-1st millennium, and so its megafauna survived longer than their European and American counterparts. However, by about 1600, the elephant bird, along with giant lemurs, the giant fossa, and giant tortoises, were extinct.

Answer: moa

Like Madagascar, human arrival in New Zealand occurred very recently. While Australia has been inhabited by humans for around 40,000 years, the first humans to reach New Zealand were the Maori, who arrived around 1300. Within 200 years, all species of the moa, as well as the Haast's eagle, had been driven to extinction.

Answer: tinamou

In many textbooks, you may find a reference to "ratites and tinamous", as it was assumed that flightlessness evolved only once, after the tinamous had already diverged from the rest of the ratites. However, DNA evidence shows that ostriches are the most distant from the other ratites, with the rheas diverging second. The rest of the ratites can be split into two related groups: the moas and tinamous, and the elephant birds, kiwis, cassowaries, and emus. Among the last group, the elephant birds are closely related to kiwis, while the cassowaries are closely related to emus.

While tinamous can fly, they spend most of their time on the ground, and prefer to walk or run rather than to fly

Answer: False

Divergent evolution refers to one species evolving into multiple species due to different adaptations. Convergent evolution, on the other hand, refers to different groups independently evolving the same adaptation, which is the case in the ratites.

In order for ratite flightlessness to be an example of convergent evolution, as had been previously assumed, the tinamous would have had to re-evolve the capability of flight after losing it, which has never before been seen in any avian species. On the other hand, birds losing flight is common, as the adaptations needed for flight are costly, and thus are often discarded when no longer needed. Given the position of the tinamous in the ratite family tree, it seems that flightlessness evolved at least three separate times, and possibly as many as six.