EVERYDAY SCIENCE

Detailed explanation-1: -In this spring breeding season, adult crabs typically attract one another using pheromones (chemical scents). In some species, such as the blue crab (Callinectes sapidus), males will release pheromones and then use their claws to fan the scents toward prospective females, sometimes while moving side to side.

Detailed explanation-2: -Sea creatures, such as crabs, use a range of different senses to find their way around their environment. One sense that researchers are finding important is sound. Instead of navigating by what they see, crabs can navigate by what they hear. Crab larvae are able to tell a good habitat by what it sounds like.

Detailed explanation-3: -Eggs are fertilized as they pass out of the crab’s body and are deposited under the apron. The apron is actually the curled-under abdomen, and has small appendages to which the eggs attach. Egg masses have an average of two million eggs, and can have up to eight million eggs.

Detailed explanation-4: -Sex identification The abdominal flap of each crab was observed to determine the sex. In male S. olivacea, the abdominal flap was narrower like a “V” shape, female crabs had a wider “U”-shaped abdomen, and hermaphrodite mud crabs had irregular abdomens (Fig.