Myomorpha

Myomorpha is an infraorder within the order Rodentia. It groups the majority of the so-called mouse-like rodents and includes two superfamilies, Muroidea and Dipodoidea. This clade is the most species-rich and ecologically diverse within Rodentia, with thousands of living species occupying a wide range of habitats.

Representative members include the common house mouse (Mus musculus) and the brown rat (Rattus norvegicus), as well as voles and lemmings (various genera within Cricetidae and Microtus), hamsters (Cricetinae), and gerbils (Gerbillinae). The Dipodoidea include jerboas and jumping mice (families Dipodidae and Zapodidae). Together, these groups comprise the bulk of rodent diversity, distinguishing them from more distant rodent lineages.

Taxonomically, Myomorpha is placed as an infraorder within Rodentia. It is defined by a distinctive pattern of cranial and dental features, including the arrangement of jaw musculature and dentition that differentiate these rodents from other subgroups such as Sciuromorpha and Hystricomorpha. The fossil record for myomorphs extends back to the early Cenozoic, with significant diversification during the Miocene in many regions.

Ecology and distribution: Myomorphs are found on most continents (except Antarctica) and inhabit forests, grasslands, deserts, and urban environments. They are often opportunistic, with high reproductive rates and adaptable lifestyles. A number of species are important as agricultural pests or disease vectors, while others are of conservation concern due to habitat loss or population declines.