Litinsects

Litinsects #32: Circulatory System Sadly today’s picture has nothing to do with the post’s content but what I’m explaining today is kind of hard to photograph... the insect circulatory system Ever wondered why insects don’t bleed red? Insect “blood” is actually called HEMOLYMPH. It does not contain iron-based hemoglobin or red blood cells like we rely on for oxygen transport so it’s usually yellow/green/gray i n color Their circulatory system plays no role in gas exchange. As I explained in a previous post, insects breathe via their tracheal system, which is a network of small tubes with openings along the side of the body Insects have an OPEN CIRCULATORY SYSTEM, meaning their hemolymph is not contained within blood vessels. Instead, their tissues are bathed in hemolymph. One DORSAL VESSEL, a tube along the insect’s back, is responsible for the movement of hemolymph throughout the body through the contraction of muscles Like with our own circulatory system, res...

© Christopher Marley Litinsects #9: Beetle Biodiversity Take a minute and think about all the different animal species that science has named... from sponges and snails, to earthworms and scorpions, to sharks and birds and humans. What if I told you that a quarter of all the animals that we know of right now on this planet 🌍 ... are beetles?! I know it’s hard to imagine...all the people... living life in peace... oh wait, wrong kind of beetle! 😜 There are around 380,000 named beetle species at the moment. They make up about 40% of all insect species but scientists think there could be a MILLION more beetle species that haven’t been discovered yet! They are found in almost every type of habitat except polar regions and the open ocean and come in all shapes, colors, and sizes imaginable. Now for some fun beetle superlatives: The HERCULES BEETLE is the longest beetle and one of the largest flying insects in the world, measuring up to 17cm (7 in). It can lif...

Litinsects #2: Beetle Elytra Beetles, like this ladybug here, come in all shapes and sizes but have one basic thing in common: hardened (sclerotized) forewings, named ELYTRA, which cover and protect their bodies. In flight, the elytra are lifted up and the hindwings are extended so, functionally, beetles actually only use one pair of wings to fly. Now for some FACTS about beetle wings... 🐞 The scientific name for beetles is COLEOPTERA, which comes from the Greek koleos, meaning sheath, and pteron, meaning wing Elytra are not “used in flight” per se but do have an effect on lift and drag. They also serve to TRAP MOISTURE and keep the hindwings from dehydrating Beetles’ hindwings are usually much longer than their elytra. At rest, they are FOLDED longitudinally (the long way) and then transversely (across) and tucked under the elytra (see second picture) Most insects fly with their legs tucked against their bodies to reduce drag but beetles fly...