General

The cancer - Wanted poster


Characteristics

Surname: Cancer
Latin name: Brachyura
class: Higher crabs
size: 5 - 10cm
mass: up to 500g
Older: 5 - 15 years
Appearance: yellowish, reddish, brownish
Sexual dimorphism: No
Nutrition type: Omnivore (omnivor)
food: Carrion, algae, fish, crustaceans, molluscs
distribution: worldwide
original origin: unknown
Sleep-wake rhythm: diurnal
habitat: Fresh water and salt water
natural enemies: Fish, octopuses, crustaceans, birds
sexual maturity: after 1 - 2 years
mating season: depending on the species
Threatened with extinction: No
Further profiles of animals can be found in the Encyclopaedia.

Interesting about the cancer

  • The size of crabs is enormously variable depending on the species: Japanese giant crabs reach a length of 4 meters and a weight of 20kg. In contrast, the microcrab is a maximum of 1cm in size.
  • Worldwide, one estimates the species diversity of the crabs at about 6500. Including u.a. Crawfish, lobster, lobster or beach crab.
  • The majority of all crab species have two distinct scissors. Crabs use the scissors to defend themselves against predators, but also to fight against fellow members. In the fight for females, it can happen that a crab separates the scissors from their conspecifics.
  • Male crabs are usually up to 20% larger than their female counterparts.
  • The female carries the fertilized eggs at the beginning of embryonic development on the underside of the abdomen. With the beach crab, such a "packet" can contain up to 150,000 eggs. More than 95% of the crabs are eaten even before they become sexually mature.
  • Crabs move sideways in the countryside. This is - for anatomical reasons - the fastest method of locomotion for a crab.
  • The outer skeleton of crabs consists of lime (calcium carbonate).
  • The first crabs lived more than 200 million years ago in the oceans.
  • Cannibalism among crabs is a frequently observable phenomenon. Larger crabs eat younger, regardless of whether they are identical or dissimilar.