Although there are many species of rats, there are essentially two kinds of rats, Rattus norvegicus; the Norway/street/common/home rats, which are generally brown in color and Rattus rattus the roof rats that are black in color.
Rats certainly have a bony skeleton like other mammals, together with the bones connected by joints and cartilage. A great deal of people wonder if this is truly so because of how nimbly the rat runs as it flees and the way the sizable rat can fit through a surprisingly little hole. Sometimes, they appear to be wriggling in a fluid manner like an eel. This feature enables the rat to invade allegedly secured spaces in human dwelling and makes their removal comparatively tricky.
It's been postulated that rats have collapsible bones, or bones which may bend for all those movements, but those aren't correct.This has to be placed in consideration while rat-proofing your homes. It's strongly recommended that you use a 1/2 inch by 1/2 inch net when obstructing entry hole as wire mesh with 1 inch by 1 inch holes wouldn't be evidence against small rats.
The main reason that rats can fit into these smaller holes is that they have long bodies, pliable and flexible shaped. They also have powerful legs and they don't have collar bones. All these are adaptations for their burrowing lifestyle.c
They typically assess the magnitude of a hole with their nose and whiskers, to decide if they could match, or dart off to another hole. On occasion though, it's possible for a rat to get stuck mid-way through a hole because of miscalculation in haste or being obese. Overweight rats have additional fat around their abdomens and will be not able to fit through the very same holes as their healthy counterparts.c
So as to get rid of rats on your house, you have to inspect it thoroughly, identify all of rat entrance points and block them. Watch out for tell-tale signs of rat existence, e.g. scratch marks, foul odours, scurrying sounds, faecal remains, signs of harm. Enlist the support of a professional if you would like to be sure.