Where do mice come from? - briefly
Wild populations of the species «Mus musculus» have historically inhabited fields, forests, and grasslands, later colonising human dwellings as opportunistic commensals. Their distribution expands via natural dispersal, agricultural trade, and inadvertent transport in shipments.
Where do mice come from? - in detail
Mice originate from the family Muridae, a lineage that diversified during the late Eocene epoch, roughly 35–40 million years ago. Fossil records indicate early murine species inhabited forested regions of Eurasia, later spreading across continents through natural corridors and, subsequently, human activity.
The primary mechanisms of distribution include:
- Natural migration along river valleys and mountain passes, allowing colonization of diverse habitats.
- Accidental transport in grain shipments, timber, and other goods, facilitating introduction to new continents.
- Intentional release for laboratory research, leading to established feral colonies near scientific facilities.
Wild populations thrive in environments that provide shelter, food, and nesting sites. Typical habitats comprise fields, forests, and urban structures where cracks or debris offer protection. Reproductive capacity contributes to rapid expansion: a single female can produce up to ten litters annually, each containing three to twelve offspring, resulting in exponential growth under favorable conditions.
Genetic studies reveal that modern house mouse subspecies—such as Mus musculus domesticus in Europe and M. m. musculus in northern Asia—share a common ancestor that originated in the Indian subcontinent. Subsequent divergence occurred as groups migrated westward and eastward, adapting to local climates and resources.
Human settlements have amplified the presence of mice by providing abundant food waste and heated interiors. Consequently, the species now exhibits a cosmopolitan distribution, inhabiting virtually every continent except Antarctica. The combination of ancient evolutionary origin, high reproductive rate, and anthropogenic dispersal explains the widespread occurrence of these rodents.