Ancestor: Desert Mountain Scraping MiceÂ
Evolved: By 2 Myh
Extinct: Not yet.
Location: Middle latitudes grassland to desert climate zones of West Catland.
Viable Habitat: Different types of deserts including sandy deserts and dry mountain plateaus. Is moving into grassland habitats.
Size: Genus average 8cm nose to back of hindquarters (15cm including tail)
Dietary Needs: They have an omnivorous diet, with the bulk being seeds, grains, invertebrates and to fuel their energy, fruit. Sugar is a rare but important resource, only offered seasonally by date palms, the fruit of their parasites belonging to tillandsia, and arid-adapted elders. They also love honey, but rarely can they actually reach it without being stung to death by bees. For out-of-season they must make dry fruit stashes, mostly of dates (sometimes entirely dates). Where palms grow in tight clusters may previously have been a mouse's stash that was forgotten and germinated. The animal component of their diet is usually invertebrates, from insects to worms.
Life Cycle: Adults of most species guard a territory to avoid food scarcity from crowding. However in certain greener areas there are species that live semi-communally, still keeping their own individual nests but keeping lookout for each other. In some such situations one male (usually one already successful in many respects such as mating and territory guarding) might drive off the other males so he has a whole commune of females to himself. These communes are incredibly rare in resource sparse locations such as deserts. They are also usually temporary as poorly productive years will cause them to scatter. Thus inbreeding isn't an issue.
They are very fast growing, needing a constant intake of fatty invertebrates such as mealworms, annelid worms, snails and woodlice once they start eating solids, which is within about 5 days of being born. Because of this they only breed in the wet seasons when invertebrates are also breeding at their highest numbers. The mice are done growing within a month, and sometimes have their own pups in that much time. Despite the productive seasons being so short at some parts of their range, their short breeding cycle allows for more than one generation to be born in a season.
Other: Males "sing" in ultrasonic chirps and warbles at a frequency that is inaudible to cats (over 60,000 kHz). Females also use these ultrasonic frequencies at a low volume to communicate with other mice and their own offspring but males are the only ones to use loud songs to attract females, or advertise to other males to stay away or they'll get more than they bargained for. Also, not having parental roles for the most part, males can focus more attention on being ready to sound the alert for cats and other predators that would pounce his females caught off-guard by attending to offspring.
These mice are faster and springier with their extended foot and improved articulation of the ankle joint. They can also rear up on their hind legs when on the alert, with some species using their tail for support.
Most of their movement is on all fours and they can run just as well as their ancestors did on all fours. However, they can also hop forward (both feet simultaneously) on their hindlegs at great speed when quadrupedal running isn't enough. Not only is this faster but it adds a bouncing motion to their path of movement, which makes them a less predictable target than if they were moving in a smooth path.
The hopping is also energy efficient and allows them to cross large areas of featureless desert to reach resources distances away, without becoming too exhausted. They typically travel and forage at night and are rarely out during the day. Their vision is better at night and their hearing is also very sharp as they may be hunted at night by cats, birds and lizards.