Basically there are no difference between a Rat and a Mouse in view of scientific classifications. These are two commonly used names to relate similar looking rodents.
Rats are the medium –sized rodents that have thin long tails. Most of the rodent species are referred to as rats- cotton rats, kangaroo rats, black rats, naked mole rats, Norway rats, wood rats, pack rats, African pouched rats and more are the commonly known names given to the different species of rats.
Mouse is the name used to describe sparrow-sized small rodents with thing long tails. Similar to that of rats, there are several species called mice, which can be closely related to one another; field mice, house mice, smoky mice, deer mice, dormice, spiny mice and more.
When it comes down to the discussion of mice and rats, people are usually interesting in understanding the difference between mice and pest rats (domestic rats). The two commonly found families of both in urban location are Norway rats and House mice.
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House mice are 12-20 cm long and have a weight of 12-30 grams. They are typically found to be in gray or brown color. The snouts of house mice are triangular with long whiskers. These rodents have thin, long, hairy tails with large floppy ears. Mice can survive in all climates, however, they mostly prefer living in heated locations where more water and food can be accessed. The life expectancy of mice is higher than rats, giving them three to six years in captivity. Urban mice, on the other hand live less than one year. This is due to the fact that mice are territorial and timid in nature.
Rats, on the other hand are large to medium-sized rodents with long and thin tails, commonly scaly and hairless. Rats are also found to survive in different climates. By nature, rats are nocturnal. Rats can grow up to 40 cm long and usually weigh more than mice. The coats of rats are gray, white, black and brown in color. Rats are soiled, and are likely to leave grease marks on surfaces they touch. Their snouts is blunter than a mouse.
What makes both mice and rats a wearisome pest is the breeding habits of both. In favorable conditions, a heavy rat or mouse infestation can be on a go. The babies of both mice and rats are born hairless and blind.
The survival of the babies depends on the breeding, health and age of the mother. A female rodent who mates with a different species of rat/mouse, is likely to give birth to dead infants. Similarly, a female rat/mouse in her menopause period produces smaller size of babies. The growth and survival on these depend on the environment they are living in.
Here we find some other specific difference between a Rat and a Mouse according to www.in.gov