Equus (genus) 54 million years ago (Mya). These animals had three toes on the hind feet and four on the front feet with small hooves in place of claws, but also had soft pads.<ref name="doi10.1126/science.1105458"></ref> Equids developed into larger, three-toed animals (e.g. "Mesohippus") during the Oligocene and Miocene. From there, the side toes became progressively smaller through the Pleistocene until the emergence of the single-toed "Equus". The genus "Equus", which includes all extant equines, is believed to have evolved from "Dinohippus", via the intermediate form "Plesippus". One of the oldest species is "Equus simplicidens", described as zebra-like with a donkey-like head shape.
Aedes africanus virus, West Nile virus, and Rift Valley fever virus. It is also a vector of Zika virus, the causal agent of Zika fever. Aedes africanus Aedes africanus is a species of mosquito that is found on the continent of Africa with the exclusion of Madagascar. "Aedes aegypti" and "Aedes africanus" are the two main yellow fever vector species in Zambia. "Aedes africanus" is mainly found in tropical forests not near wetlands. This mosquito has distinct white and black stripes along its body which help differentiate the genus from others in this family. Females of this species are ectoparasites and can