Figure 3

Interspecies phylogenetic relationship of marine, amphibian, reptilian, avian and mammalian species. The PrP^C instability index (II) is recorded next to each reported species. The colours in the phylogenetic tree represent different taxonomic groups of animals, helping to visually distinguish their evolutionary relationships: (i) Blue: Represents aquatic species, specifically fish and amphibians, such as the Japanese rice fish (Oryzias latipes), zebrafish (Danio rerio), and African clawed frog (Xenopus laevis). (ii) Light-Green: Represents reptiles and birds, including species like the king cobra (Ophiophagus hannah), saltwater crocodile (Crocodylus porosus), and wild turkey (Meleagris gallopavo). (iii) Yellow: Represents monotremes and marsupials, such as the platypus (Ornithorhynchus anatinus), common wombat (Vombatus ursinus), and Tasmanian devil (Sarcophilus harrisii). (iv) Green: Represents placental mammals, including humans (Homo sapiens), elephants (Loxodonta africana), and mice (Mus musculus). (v) Orange: Represents various mammalian species with higher protein instability index (II), such as dogs (Canis lupus familiaris), rhinos (Diceros bicornis), and whales (Balaenoptera acutorostrata scammoni).