Living in Maine, where lobsters are available left and right, I’ve always thought that they resembled something I’ve seen before…something I’ve seen way too many times and never particularly enjoyed. Those exoskeletons…the many legs….the antennae…could it be that the lobster is similar to a common co*ckroach? Are some of us eating insect meat for dinner?! The American Lobster,Homarus americanus, is a crustacean found along the Atlanticcoast of North America. Crustaceans shares a common ancestor with all insects, including the household co*ckroach,Blattaria.
Insects and crustaceansbelong to the phylum Arthropoda. Theclass Insecta, contains insects (no way!) such as mosquitos, beetles, and ants. Insects allhave six legs, twoantennae, three body parts, and most have twopairs of wings. Thesix legs of a co*ckroach serve as a locomotor system, which gives them the ability to run under couches,refrigerators, or old baseboard molding. Insectsbreathe through a tracheal system, which brings oxygen in air to their cells, through tiny tubes with openings at on the sides of each body segment. Many insects are short-lived creatures, but some, likecicadas, can live for more than a decade! Lobstersare comparatively very long-lived creatures. They can live up to 50 years in the wild!
Lobstersalso belong to the phylum Arthropoda, but are divided into thesubphylum Crustacea, which encompasses other familiar organisms such as crabs, shrimp, and krill. Their bodies are a bit like a Swiss Army knife: they have an appendage for every job!They have 10 legs for walking, and 2 pairs of long antennae-likeappendages used to feel and smell (yes, smell) their surroundings.Their two impressiveclaws are used for both acquiring food, defense, and in territorial disputes with other lobsters.Arthropods don’t have a hinging jaw, like we do, instead they have several pairs of specialized “mouthpart” appendages that help them manipulate food, chew and grind it up, and sweep it into their mouths. The bottom side of their “tail” is coveredin several fringy appendages and ends in a fan-shaped telson. These swimmerets help the lobster swim above the seafloor, and when combined with a fast flick of the tail, they allowit to make a quick backwards escape from danger.
Since lobsters and most other crustaceans live underwater, they can’t breathe in the same way as insects. This is because while air has a lot of oxygen (21% of air is O2), seawater is mostly… water (shocking I know!). So lobstersabsorb oxygen from the water with 20 pairs of gills. These are hidden under the shell at the middle of the body, and the animal continually sucks water across them. Other crustaceans have more exposed gills, typically at the base of the legs. The fact that crabs (like the lobster) have well-protected gills, is probably why more crabs have evolved to live on land than other crustaceans.
Although these organisms appear to be very different, plenty ofevidencesuggests that the lobster and the co*ckroach are more similarthan many people might think! They are both arthropods with segmented bodies, exoskeletons made of chitin, and a need to molt as they grow. Both groups have compound eyes, jointed legs, and muscle fibers gathered into bands. (Is that why they taste good?) On a more superficial level,lobsters and co*ckroaches are both active at night andomnivorous,consuming a wide variety of foods.And while the arthropod phylum contains lots of other creatures, such spiders and centipedes, anatomical and DNA evidence all support the idea that insects and crustaceans are more closely related to one another than to the other arthropods.
It may therefore not be so weird to think of lobsters as ‘co*ckroaches of the sea.’ Eating insects is actually a common practice in some parts of the world, and it maybe good for global sustainability, since insects can be grown usingmuch lessland area than cattle, pigs or chickens, and they produce less waste. Expanding our minds to acceptinsects in our diet mightbe a good idea.
However, don’t be too grossed out — the co*ckroach and the lobster, probablyshared thatcommon ancestor about 525 million years ago. Since then, they have evolved into pretty different creatures. Thank you, evolution!
