the species that saved me

[agent A]

so I'm writing a book, and I figured y'all may want to see some of it in advance!
so here's an excerpt:
Chapter 1: Actias luna

Moths make me tick. So much so that I think if I lost them as a special interest, I’d fall apart. They are interesting to me that 3 of them made the list. Well, 1 is a butterfly, but technically by the law of monophyly butterflies (having descended from moths) are in fact moths. I will some day tell you fine folks a bit about several other butterfly species that are near and dear to me. There are so many other moths I want to (symbolically) vomit hoards of miscellaneous knowledge about and experience with onto y’all, but we need to reign this thing in. I don’t know if there’s something inherent to moths that I’m drawn to, or if it’s that I’ve learned to be skeptical of people’s shunning of something that people generally hating moths makes me like them so much. I am also writing this at a time when I’ve had contact with 1 moth species in the last 6 months and your boi (I’m nonbinary so I’ll alternate between referring to myself as a boy or a girl) ain’t doin so hot!

Can we just zoom out on the Lepidoptera as a whole to appreciate them? Ok I guess that because fair’s fair and I didn’t write this book in order, so why would I expect to read it in order? If you want to skip ahead to the dog chapter, chapter 3, go ahead, but please come back to the luna moth chapter! PLEASE… There’s the “conventional” Lepidoptera that laypeople tend to know. You know, the ones that feed on leaves as larvae (referred to as external folivores) and nectar or nothing as adults? Well, that feeding guild (a feeding guild is basically HOW the herbivore utilizes the host plant) is one of the myriad ways larval lepidopterans feed. Some moths are so tiny that the caterpillar is small enough to fit between the layers of a leaf! These are miners. Then we have our gallers.

Imagine, if you will, the ability to give your food cancer. Now why the fuck would you want to do that? Because to you, cancer is delicious. Let me explain something real quickly. Cancer in humans is tragic because the cells of a human aren’t compatible with a human cancer. Plants aren’t confined to this. Basically, plants can tolerate a lot more genetic material and cell overgrowth than any species of animal, and so cancer does not kill plants. The plant cancer cells, however, are extra nutritious for an herbivore. This is in part because they have no defensive chemistry (something we’ll cover in the next chapter) that can harm the herbivore. So some insects and arachnids and nematodes have evolved ways to induce cancerous masses on a plant for their own benefit (food and shelter). When insects and certain mites do this to plants for food, we refer to this as galling. The gall is the big wad of plant tissue with the critter inside. We tend to associate galls with wasps and certain flies, but there are lepidopteran species that form galls on their hosts.

 

[agent A]

Diarrhea isn’t always cause for alarm in an animal. Now, it generally is a symptom of a serious problem. In most cases, an animal has diarrhea because it’s sick. Maybe it has a virus or a parasite that’s shed in its feces. Maybe it’s not absorbing the water from its colon properly. In caterpillars, however, it can be a sign that the insect is getting ready to pupate. Moths are holometabolous, meaning that they have four distinct life cycle phases. They hatch from an egg into a larva, which is a simplified form of insect biomass that’s dedicated to eating. Once enough fat reserves are built up, the larva pupates. Contrary to popular belief, the creature doesn’t fully liquify and re-form itself. Enzymes break down fats in a coordinated manner (so not all at once) and the energy from that fuels the imaginal discs, which are basically wads of stem cells that grow out into wings, legs, mouthparts, and genitals/gonads. Ok technically in most Lepidoptera the late instar (an instar is a period between molts, and we’ll get to that in the next paragraph) larvae have mostly-formed ovaries or testes, but they can’t use them until the animal is a fully-grown adult. In some species, the testicles don’t turn out sperm for some time after adult emergence. Before a moth larva can pupate, however, it has to purge. The digestive tract would decay if left full of really watery, partly digested food. So the insect has a bit of really squishy diarrhea right before it spins the cocoon or burrows or clings somewhere to pupate. If your caterpillars are in the final instar and are about full-size, they’re about to pupate and the diarrhea (that’s still really not so fun to clean up) is not abnormal.

Insects are unlike us humans in many ways. One of the more important distinctions is that insects and their allies are covered with an external skeleton. There’s a rigid “shell” coating the body, which protects it and gives it structure. We humans have an internal skeleton that adheres to our tissues for structure and support. Insects have a major problem caused by their exoskeleton, though. Unlike bone, the outer casing of an insect is not capable of growth. So it must be cast off every so often. This process, called ecdysis or molting, is a fun one indeed. First, the living cell layer underneath the exoskeleton is pulled away from the outer casing. Then, the insect breaks the exoskeleton and climbs out of it. Afterwards, the insect pumps air and blood into all of its body parts to stretch them. It must stretch them a fair amount and it must do it within about 20 minutes before the exoskeleton once again becomes rigid. The new spaces within the body are now prime for cell growth within them, and then when these gaps are once again filled, the cycle repeats. When an insect hatches, it’s said to be in the first instar, often noted as i1 or L1. In a hemimetabolous insect such as a roach or a praying mantis, it’s i1. In something like a moth or a beetle, it’s usually called L1 (L for “larval”). The number of instars a species has is dependent on the taxon. Beetle grubs and maggots tend to have 3 larval instars because their exoskeletons are a lot softer and more flexible, and thus can stretch a bit more before the creature must molt. Things that live in more concealed settings like a rotting log or a nasty carcass tend to be like this. Meanwhile, the majority of Lepidopterans have 5 larval instars. Their skins are a bit less rigid than those of mantises and other really active critters, but not as soft as beetles or maggots. Some mantis species, in contrast, have up to a dozen nymphal instars (although the average is about 7). Tiger moth larvae, who are a lot more motile than something like a luna moth larva, have 8-12 instars. Some species are capable of increasing or decreasing their number of instars depending on environmental factors (especially nutrition), and in many species, females have 1-3 extra instars. What sets insects apart from basically every other molting animal out there is that (with the exception of a few mayfly species) they stop molting after they reach sexual maturity. In animals that continue to molt after reaching sexual maturity, they have to fit their breeding in with their molt cycle. Some creatures, like crabs and isopods, must mate within a mere few hours of molting, because the opening of the female that takes up sperm (which is often a different opening than where the eggs come out of) gets covered up toughened exoskeleton. So, the female will molt and the male will insert the sperm where it belongs, pushing away the skin and molding it back in place afterwards. In some species, the eggs are laid pretty quickly after. More on this in the next paragraph. In spiders, the lining of the female’s reproductive tract is shed during a molt, and so if a mating occurs just before a molt, the sperm will be lost! Insects don’t have to be as careful about this, because they stop molting once they’re capable of reproducing.

Insects are also a bit different in their way of fertilizing their eggs. In nearly every insect species, the sperm is deposited into the female’s reproductive tract and it sits in a gland (referred to as a spermatheca) that is along the “birth canal”. As a mature egg is pushed from the uterus to the outside world, a sperm is released onto it to fertilize it. If you’ve ever seen a fresh luna moth egg, you’d know what I mean. It’s really soft and a weird greenish color for about 10 minutes after the female deposits it. In most insects, sperm is delivered via a spermatophore. The spermatophore is a gelatinous sack that contains sperm and often times, a few other goodies for the female. First, most species incorporate a hormone that not only stops the female from being horny, but makes her want to go lay eggs! Sometimes, the male clogs up the female’s vagina so other males can’t get access (in about 98% of extant Lepidoptera, the female has 2 vaginas, 1 for getting the penis and 1 for laying the egg). In many species, the male also gives the female a nuptial gift. It’s often various nutrients from the male’s own body that increase the female’s reproductive output. In some moths, females that mate multiple times lay a greater percentage of their egg allotment before dying than females who only mate once.

 

[happy1892]

That is very interesting stuff! I didn't know that galls were made from cancer in the plants. I have read that plants are able to have cancer and live with it because of their cell walls, which animals and fungi don't have. I wonder whether people could make large sweet galls in the future from our wild forests like fruit trees. Do you think that would be possible with genetic engineering?

Luna moths are my favorite type of moth. There are several species of Luna moths around the world. I breed them once, but the pupas emerged during winter because I kept them indoors where they didn't get the gradual reducing of light they need to go dormant when they pupate. The gradual reduction of daylight hours is how they know winter is coming. But the Imperial moth pupae that I was raising at the same time as the Luna moths were fine because they seem to not go by the daylight hours to be dormant. I kept the Imperial moth pupae in a cool unheated wood shop.

I have had vomiting issues with Orchid mantises drinking water. Do you think that it could be that they may be lacking a symbiotic bacteria or other micro organism in their guts that could be causing this issue? If taken from their native habitat and into captivity they may loose some of their gut biome that they need. Maybe that could also be one of the causes of diarrhea? I have read that when honeybee colonies were given fungicides that they later got sick with chalk brood (a be fungus disease) because they lost their natural symbiotic fungus in their bee bread (?) or guts (?).

Would you happen to know of some moth or butterfly species that are easy to breed and could be used as feeders for mantises? I have been told that Toxodera beieri are picky eaters and only like to eat butterflies, so I was curious whether people could breed butterflies to feed them. Toxodera beieri is are extraordinary species of mantis! They mimic a gnarly branch with lichen very well! And the Toxodera integrifolia has the nice pink and yellow colours. One person suggested people calling the Toxodera integrifolia "Mushu mantis" or maybe Mushu Dragon mantis.

 

[hibiscusmile]

Interesting about the spiders, do all species do this or?

 

[agent A]

Interesting about the spiders, do all species do this or?

no. I am pretty sure CERTAIN spiders like orb weavers do have a "final" molt like insects do
there's also probably an upper limit to how many times something like a tarantula can molt in its lifetime, especially if it's a male