Lifting of this pressure and more abundant foraging opportunities would then have selected for larger size and consequent loss of flight.
So the extinction of the dinosaurs likely lifted predation pressures that had previously selected for flight and its necessary constraint, small size.
“Our study suggests that the flighted ancestors of Ratites appear to have been ground-feeding birds that ran well. Dr Matthew Phillips from the ANU Research School of Biology believed that the evolution of ratites evolved separately in different locations However, scientists highlight how ratites, being flightless, could have crossed the ocean between two isolated landmasses such as Australia and Madagascar. Alongside this, their tail and flight feathers are just decorative and have no purpose, meaning that they have no oil glands. This group of large, flightless birds are characterised by underdeveloped breast muscle, an almost-absent wish bone, a simplified wing skeleton and a palaeognathous palate. Incredibly, most ratites are now extinct.Ĭomparative studies of DNA sequences of current living ratites show that emus and cassowaries are the closest relative to the original ratites living in Gondwana. Furthermore, fossil records indicate the evolution of Ratites happened around the time that dinosaurs died out, which is around 65 million years ago. Ratites are believed to have originally come from Gondwana, the ancient supercontinent that broke up around 180 million years ago. Studies based on DNA sequences show that ratites continued to evolve into their modern counterparts as the continents seperated. 3 Other birds who are classed as ratites include the Ostrich and Emu. Despite the eye-rolls this phrase may be met by, the Cassowary actually belongs to the taxonomic order struthioniformes. This order is commonly referred to as “ratites”. With giant, claw-like feet and drooping, dinosaur-like skin, it should come to no surprise that the Cassowary is often called the “Dinosaur bird”. Ratites A modern ratite? Meet Cass the Southern Cassowary at Wildlife Habitat Port Douglas with Jungle Tours Without further adieu, it’s time for the Jungle Tours addition of Myth Busters: “Is A Cassowary A Dinosaur?” Like many things in the Daintree, the Southern Cassowary looks straight out of the pre-historic times. We answer the age-old question: “Is A Cassowary A Dinosaur?”
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