Brown rat

The brown rat is a tough, adaptable rodent found almost everywhere humans live. Originally from northern China, it now thrives in cities worldwide, scurrying through streets and sewers. These rats eat almost anything and can grow as long as a ruler.

• Their bodies stretch up to 28 cm (11 in) long, plus a slightly shorter tail.
• They’ve hitched rides with humans to every continent except Antarctica.
• A single rat can weigh anywhere between 140 and 500 grams.