- http://struthionifunfacts.weebly.com/blog/category/exemplary-organisms
- https://animalcorner.co.uk/animals/ostrich/
- http://news.nationalgeographic.com/news/2014/05/140513-flightless-birds-ostriches-moas-evolution-science/
- http://animals.sandiegozoo.org/animals/emu
- https://en.wikipedia.org/wiki/Emu
- https://a-z-animals.com/animals/emu/
- https://en.wikipedia.org/wiki/Common_ostrich
- http://www.nationalgeographic.com/animals/birds/o/ostrich/
- http://animals.sandiegozoo.org/animals/ostrich
- https://en.wikipedia.org/wiki/Kiwi
- https://www.kiwisforkiwi.org/about-kiwi/kiwi-facts-characteristics/
- http://animals.sandiegozoo.org/animals/kiwi
- https://a-z-animals.com/animals/kiwi/
- https://blogs.scientificamerican.com/tetrapod-zoology/ratites-in-trees-the-evolution-of-ostriches-and-kin-and-the-repeated-evolution-of-flightlessness-ratite-evolution-part-ii/
- https://onekindplanet.org/animal/ostrich/
- https://en.wikipedia.org/wiki/Ornithomimus
- https://en.wikipedia.org/wiki/Asian_ostrich
- https://en.wikipedia.org/wiki/Pseudocrypturus
- https://www.dkfindout.com/us/animals-and-nature/birds/inside-an-ostrich/
- https://link.springer.com/article/10.1007/BF00283247
- https://www.genome.gov/26524120/chromosomes-fact-sheet/
- http://study.com/cimages/multimages/16/karyotype_karyogram.png
- https://www.britannica.com/animal/flightless-bird
- https://en.wikipedia.org/wiki/Palaeotis
- https://en.wikipedia.org/wiki/Ratite
- https://blogs.scientificamerican.com/tetrapod-zoology/ratites-in-trees-the-evolution-of-ostriches-and-kin-and-the-repeated-evolution-of-flightlessness-ratite-evolution-part-ii/
- http://onlinelibrary.wiley.com/doi/10.1002/dvdy.22520/full
- https://www.britannica.com/animal/ostrich