Discovered by Mark Harvey, WA Museum

have a confession to make – I love Australia’s black . Whenever I I see them careen and roll above me, I get a frisson of joy. They seem to move effortlessly on gently pounding wings, calling to other members of their flock in sonorous delight. Their feeding can quickly produce a carpet of discarded gum nuts and other debris that have been torn apart in search of tiny seeds that they ingest. It’s not often that I become lyrical about nature, but these are wonderful and I feel privileged to witness their antics. Apart from the very different palm , the five of black cockatoos are placed in the , but three species, the yellow-tailed in eastern Australia and two others, Baudin’s cockatoo and Carnaby’s cockatoo, which occur Red-tailed black cockatoos only in south-western Australia, are sometimes placed in the genus Zanda. Eastern Australia’s glossy black cockatoo is C. lathami. Notably, the two northern subspecies, these populations from C. b. samueli thus However, the most widespread species C. b. banksii and C. b. macrorhynchus, could drastically reduces the known range of is the red-tailed black cockatoo (C. banksii), not be distinguished from each other, C. b. samueli, which occurs in the southern which ranges over much of Australia having remarkably similar SNP and DNA Northern Territory, and inland Queensland although it is largely absent from wetter profiles. and New South Wales. south-eastern Australia and Tasmania. The western population of the The discovery of a distinct subspecies Due to differences in size and morphology widespread arid Australian subspecies, in Western Australia raises significant (particularly in the shades and patterning C. b. samueli, was found to be genetically conservation considerations due to land of colour in females), it has been divided disparate from isolated populations in clearing impacting their food plants, into five subspecies: C. b. banksii and inland eastern, central and western parts including the double-gee widespread C. b. macrorhynchus in northern Australia, of Australia. The authors suggest that noxious weed that is regularly removed by C. b. graptogyne in south-eastern Australia, these differences are sufficient to regard landholders. C. b. naso in south-western Australia, and the western population as a distinct The research undertaken by Dr Ewart C. b. samueli in arid Australia. evolutionary unit, which they describe as a and his colleagues demonstrates the A recent study has been published by new subspecies, C. b. escondidus. unique power of molecular data to unravel Dr Kyle Ewart from the Australian Museum The name that they have chosen is the evolutionary relationships of our and the University of Sydney, and his derived from a Spanish and Portuguese precious biota. The discovery of a unique co-authors in the journal Heredity, used word meaning ‘hidden’ and refers to evolutionary lineage of cockatoos in single-nucleotide polymorphisms (SNPs or this subspecies having been ‘hidden in mid‑western Australia continues to shed ‘snips’) and mitochondrial DNA from over plain sight’. Indeed, the inclusion of the light on the fauna of a fascinating region. 100 birds across Australia. These techniques western population in C. b. samueli reflects Let’s hope that they continue to careen are remarkably powerful for discerning convergence where different evolutionary and wheel in the sky, delighting all who population structure and provide insights units have evolved similar morphological see them. into how these populations have evolved traits, and only the use of molecular data over time, much like tracing the genealogy finally resolved the puzzle. Above Red-tailed black cockatoos bask in of a family tree. Detailed analysis of the Populations of the new subspecies the warm glow as morning breaks in the sequence data found some surprising are known from the Pilbara, Murchison Central Wheatbelt. results. and Wheatbelt districts. The removal of Photo – Adrian Chesson/DBCA

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