Rats are incredibly flexible animals that can squeeze through very tight spaces by flattening their bodies. This ability allows them to access food and shelter in areas that would otherwise be inaccessible. In this article, we’ll explore the anatomy behind rats’ ability to flatten themselves and discuss examples of how they use this skill in the wild.
How do rats flatten their bodies?
Rats have a very flexible spine that allows them to compress their rib cage and flatten out their bodies. Their ribs are connected by loose cartilage that can bend and flex as needed. Rats also have collarbones that are not fused together like in humans, giving their front legs more range of motion to squeeze through narrow gaps.
Additionally, rats have very loose skin that can fold in on itself when compressed. Their shoulder blades and hip bones can pinch inwards to make the rat’s midsection narrower. Even the rat’s skull is made up of movable plates that can overlap to make their head more compact.
Combining all these anatomical features allows rats to squish and contort themselves to take on an impressively flat profile. Their bodies can become as slim as 2 inches across while flattening – perfect for fitting into tight spaces!
Examples of how rats use body flattening
Rats frequently flatten themselves in the wild to get into food sources and shelters. Here are some common examples:
Getting into buildings
Rats can flatten themselves enough to slip through cracks and gaps around doors, windows, or openings in walls. A rat only needs a 1/2 to 1 inch gap to work their way into a building in search of food and harborage.
Traversing tight tunnels
Rats regularly navigate underground burrows and pipes by sucking in their guts and flattening their rib cages. This allows them to easily travel routes that would be completely impassable for larger animals.
Accessing confined spaces
Flattening their bodies allows rats to get into enclosed spaces within walls, crawlspaces, cluttered storage areas, and other cramped voids where they can nest safely and find forgotten food items.
Crawling under doors
Rats can flatten themselves to slip beneath doors that don’t quite meet the floor. They can often even squeeze below doors with 1-inch gaps beneath them.
Getting into waste bins
By compressing their bodies, rats can wiggle through small openings of bins and garbage cans to reach any scraps and leftovers inside as a food source.
Chewing through packaging
Once inside cupboards and pantries, rats will flatten themselves to nibble through boxes and plastic packaging to get to the edible contents inside.
As these examples show, body flattening gives rats an impressive ability to access food and shelter in places that would stop other rodents. This skill is one of the key reasons rats have been so successful at spreading around the world alongside human civilization.
How narrow can a rat flatten itself?
Just how thin can a rat make itself when squeezing through a tight space? Here are some statistics on the incredible compressibility of rats:
| Rat Size | Flattened Width |
|---|---|
| Small rat | 2 inches |
| Medium rat | 2.5 inches |
| Large rat | 3 inches |
As this data shows, even large rats can flatten themselves down to a width of around 3 inches. This allows them to fit into unbelievably small cracks, holes, and openings throughout structures.
Skeleton adaptations
Rats have several unique skeletal adaptations that allow them to compress their bodies so dramatically:
Unfused ribs
A rat’s ribs connect via flexible cartilage, unlike the fused ribs of humans. This allows their rib cage to collapse inwards when squeezing through narrow spaces.
Collarbone separation
Rats have two separate collarbones rather than one fused breastbone. This provides more flexibility and range of motion in their front legs.
Overlaping skull plates
The skull of a rat consists of movable plates that can overlap and condense the overall size of the head.
Pinchable midsection
Rats have a narrow midsection between their rib cage and pelvis that can “pinch” inwards significantly when flattened.
These special skeletal adaptations allow rats to contort their bodies vertically and horizontally when needed. Their bones provide the compressibility that other animals lack.
Muscle structure
Beyond skeletal adaptations, rats also have muscles optimized for flattening their bodies:
Dorsal muscle anchoring
Rats have dorsal muscles anchored far down their spines rather than just at the top. This allows the spine to flex in more areas.
Repositionable front limbs
Rats can splay their front legs out to the side when needed, thanks to unattached collarbones. This reduces width.
Thick abdominal muscles
Powerful abdominal muscles help rats actively pull their midsection inwards when flattening the body.
Loose skin
Rats have very loose, flexible skin that folds inward easily when compressed instead of restricting movement.
These special muscle arrangements maximize how narrow rats can make their bodies when squeezing through small spaces.
Behavioral adaptations
Aside from physical adaptations, rats also exhibit behaviors that facilitate body flattening:
Seeking narrow paths
Rats intrinsically seek out the narrowest possible openings and routes when exploring an area.
Twisting movements
Rats make corkscrew-like twisting movements to reorient themselves and minimize their profile.
Backing into gaps
Rats often back into tight spaces, allowing them to see and control their body position better.
Slow cautious movement
Rats move slowly and deliberately when flattening themselves, carefully assessing openings and methodically working their way through.
These behaviors help rats fully utilize their physical adaptations to flatten their bodies and access confined spaces.
Developmental factors
Interestingly, a rat’s ability to flatten its body develops gradually after birth:
Limited flattening at birth
Newborn rats have very limited ability to flatten themselves, despite their specialized anatomy.
Increasing with age
As rats grow over their first few weeks, they gain strength and flexibility allowing them to flatten more.
Adult capability at 3-4 weeks
By 3-4 weeks old, rats have reached their full adult capacity for compressing their bodies.
Practice and experimentation
Young rats seem to actively practice flattening as they explore, helping perfect the skill.
Body flattening capability in rats develops steadily during their juvenile growth phase until reaching the impressive levels seen in adults.
Conclusion
In summary, rats are highly adapted for flattening their bodies to access narrow spaces. Key factors enabling this ability include:
- Flexible spine and ribs
- Separated collarbones
- Compressible skull
- Pinchable midsection
- Anchored dorsal muscles
- Loose skin
- Seeking narrow openings
- Cautious deliberate movement
- Gradual development after birth
This unique skill allows rats to exploit food sources and shelters that are inaccessible to other rodents. Next time you see a rat vanish into a tiny crack or crevice, you’ll understand the special anatomical tools that allow it to compress its body down to such an impressively flat shape!