Nightmarish Nature: Cannibalism
Let’s return to explore more Nightmarish Nature, shall we? This segment focuses on cannibalism, as we generally find it icky / taboo and because it’s more common than you might think. There are many different reasons that different creatures engage in cannibalistic practices. Energy waste doesn’t last long in nature; gaps are filled as things evolve to utilize whatever resources are available to meet their own needs. C’est la vie (light up another cigarette). In any case, the challenge to the cannibal lies in determining kinship and not accidentally erasing their own line or progeny, thus decreasing their likelihood for survival over generations. Oh, and in avoiding those pesky prion diseases…
Resource Driven Cannibalism
Resource driven cannibalism can occur when competition for resources is high. This may be due to scarcity, with individuals taking to eating each other to avoid themselves starving to death (with those consumed either still alive and killed to this end, or eaten after death of other causes). Or it may be outside of the cannibal’s control, considering the spread of Mad Cow Disease from feeding beef meal harboring the prion disease (and parts from other mammals like sheep) to growing cattle to save money, ’cause it’s not like the cows were allowed to order whatever they wanted. Or it may be due to direct conflicts with other groups of the same species, either due to competition for resources, mating rights and/or territory. These behaviors have been noted in mostly male chimpanzees raiding other groups, which have even been documented as all out wars against other males in neighboring bands, campaigning to eradicate all outside of their ranks.
Social Demonstration
Thinking about chimpanzees, males are also documented to gang up on alpha males seen as too controlling or sadistic, with groups of younger males attacking and rendering the alpha male to pieces, often consuming his flesh and blood in the process. This can upend established hierarchies to replace them with new structures, for example with a new male taking on the role of leader. But cannibalism can also be used to reinforce existing hierarchies, as seen in African Wild Dogs wherein the dominant pair will kill off any offspring that other dogs may have birthed so that the pack will focus on raising only the alpha pair’s pups, thusly reestablishing and enforcing social structure while ensuring the best survival chances for the pups raised by channeling all resources to the one brood.
Infanticide & Filial Cannibalism
Like African Wild Dogs, other parents may also eat their offspring, or better yet their rivals’ offspring. Stillborn or unhealthy offspring may be consumed, or just any that they can get their hands on at birth. (Again with the young male chimpanzees…) Some creatures enter into cycles wherein smaller individuals are more vulnerable to predation by larger ones both within and outside of ones own species, as is seen among many fishes with eggs and smaller fishes playing an important role as prey to larger ones. Other creatures may engage in these practices to reduce competition (for themselves and/or their offspring) and/or increase opportunities to mate. Male cats are notorious for killing kittens that are not their own in order to bring females into heat again sooner, potentially increasing the likelihood of mating with said females themselves while decreasing future competition. Win-win! Female cats must take great care to hide their kittens in order to protect them from males as much as other predators, and can have kittens by different fathers within the same litter in order to increase their kittens’ overall survival as a group with father cats more willing to accept kittens when their own kin are present.
Sexual Cannibalism
Mantids and spiders are especially known for sexual cannibalism, with larger females consuming males during copulation, but this is not always linked to vast size differences and does not appear in every species. Females who engage in this practice may have healthier eggs in larger clutches, thus increasing the survival likelihood of more of their offspring. Sometimes the risk to the male suitor of being mistaken for another species by an aggressive would-be mate is high, and various rituals have developed within certain species to help avoid such mistakes and entice the female to mate. Male spiders are known engage in elaborate dances, movements, tapping and silk spinning rituals to avoid being eaten pre-copulation or at all. It’s a hell of a lot more involved than a good pick up line and a well-timed drink, as you can see here.
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Thank you for joining us for another exciting episode of Nightmarish Nature. If you enjoyed this, please feel free to check out these previous segments:
Sometimes it pays not to be seen, especially if there are things that want to eat you or if you have to sneak up on things to eat them. So this time on Nightmarish Nature we’re going to look at some of the creatures known for being invisibles among us. Some of these critters engage in mimicry, intentionally looking like other specific things, but a lot of them engage in camouflage, just wanting to blend in. In this segment we’ll consider both but focus more on the latter.
Buggin’ Ya
Some of the most notable invisibles are masters of camouflage in the insect world… Moths and beetles that look like bark or dead leaves. Mantids and other insects that look like leaves or flowers. Those stick bugs and walking sticks that I’m not sure how to classify (are they some kind of weird relations to assassin bugs or their own thing?). And my personal favorite, Umbonia Crassicornis, a type of tree hopper better known as the thorn bug. And don’t even get me started on spiders and scorpions… You could come face to face with pretty much any of these critters while mucking around in your garden and be none the wiser for it unless their movement betrays their location or you happen to scan the area with a blacklight before you dig in. It’s jump scare central, for sure!
Leapin’ Lizards
Lizards and amphibians are also masters of disguise, often resembling their surroundings much like the insect world does. Chameleons are celebrated because of their ability to change color to match their surroundings, but there are several lizards that do this, just not to that extreme. Like anoles. Take a trip to Florida and you’ll soon find that you’re being stared at by a lizard you didn’t even know was there, seeing as how anoles are everywhere and get into everything (one recently startled my mother after making its home in a hallway decoration). You don’t even have to go to Florida, they range anywhere from Texas to North Carolina, and there are other lizards that range further north that do this as well.
Cunning Cats
All those coat patterns you see on cats and other ambush hunters aren’t just for show – the spots and stripes allow our feline friends to blend into their surroundings while on the prowl. Sneaky sneaky. This helps them to be the amazing hunting machines that they are. Assuming they don’t raise the bird alarm and draw attention to their whereabouts. Because birds do love to raise a stink when there’s a feline predator about, and we can’t say we blame them.
Aquatics
Then when you go underwater, you take it next level. Camouflage is taken up a notch with seahorses, nudibranchs, and more that look exactly like random flotsam. Some critters, such as Majoidea crabs, even decorate themselves with ocean debris to blend in. And octopuses are like underwater chameleons on steroids that also utilize their surroundings to create a sort of protective armor that blends in, like when they carry anything they can grab to protect their squishy selves when sharks are about. There are even true invisibles like shrimp, fish, and jellyfish that are actually clear except for their internal organs that don’t necessarily register with everything floating about underwater. Even whales can appear to come out of nowhere depending on your angle to them to start with!
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So, now that it’s getting cold, here on Nightmarish Nature we’re going to talk about a different kind of terror – the starvation diet. It’s winter, and food is becoming ever scarcer, so many creatures will slow down to conserve energy. Let’s take this a step further to the sleep of the damned… But I’m not talking hibernation, or settling in for a sort of long winter nap version of seasonal affective disorder on steroids. No, I’m talking hummingbirds.
Sugar Rush
Hummingbirds are about the polar opposite of what you’d think of when you talk about inactivity. They’re more the picture-perfect speed demons. And yet, due to their crazy high metabolisms and constant need to refuel by consuming all the nectar and insects they can get their little beaks in or on, they have near death experiences on a regular basis. Even during the summer at night whenever the temperature falls too low. It’s like all their systems have to go offline for a bit just so they can survive.
Energy Suck
Essentially a hummingbird burns so much energy that he can die in less than eight hours of not eating. The little sugar daddy needs another fix just to keep going. This lifestyle is a far cry from the Energizer bunny. Essentially he has to enter a torpor state in sleep so he doesn’t succumb to his own starvation diet. Not every time, but when the temperature drops or food is scarce.
A hummingbird in torpor may, by all accounts, appear dead. He can be frozen in place, his tiny feet clasped rigidly around a branch as if rigor mortis has sunk in. He can be cold to the touch and unresponsive. He can face upwards, unmoving, breathing and heart rate slowed to near indiscernibility. He can even be hanging upside down, oblivious to the world. In fact, the hummer’s heart rate can reduce to almost one tenth of his waking state, and his temperature can drop by ~5o degrees Fahrenheit (~ 30 degrees Celsius).
Miracle Mavericks
Honestly, as shown in this article on Journey North, this ability to exercise such fine control over metabolic rate on a nightly cycle makes the hummingbirds more marvelous than terrifying, switching between cold- and warm-blooded. And they are very well-adapted to their eating regimens, especially given their diminutive size. But such is the cost of burning so much energy to keep going without much room to store fuel. Like I said, a strict starvation diet.
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This time on Nightmarish Nature, in honor of Thanksgiving, we’re exploring scads of scat! And not just because of the aftermath of all that eating we’re going to be doing, given that everything that goes in must come out eventually. But because turkeys are weird.
But, how weird?
Apparently, the shape and size of a turkey’s poop can tell you the sex and age of the bird. Male and female birds poop different shaped turds, and bigger ones with age. Your poop can’t do that, we’re pretty sure. And no, we don’t want to check, even if it does come in a whole host of rainbow colors with all the dyes in our food nowadays. Keep your weird quirks to yourself.
Fecal Fetishes
Vultures have very acidic scat that helps to keep their feet and food clean of bacteria from hopping in and around dead things. Somehow, this doesn’t seem like a step up to us, but I guess if you’re a carrion crawler you take what you can get. At least you’d know where it’s been I suppose, and that’s more than you can say for some of your long dead food sources…
Rabbits must process their food twice in order to break down the grassy matter they digest (like cows chewing cud). And so they eat their own partially digested matter, the cecotropes they produce after the first digestion. This isn’t true poop per se, that fecal matter comes after second digestion, but it does work its way through the same way.
And that brings us to koalas. They are one of only a few mammals that can eat eucalyptus leaves (and are closely related to wombats, one of the other two). Koala offspring eat their mother’s pap, which is a specialized form of poop that allows the baby to transition from nursing milk to eating solid leaves. It is green, smeary, mushy, and can get everywhere. Just like you’d expect.
We aren’t exempt.
For all that we have learned to be poop averse, a lot of animals eat others’ scat and glean a lot of nutritional value from their detritus. It’s not just your dog raiding the cat litter box and then licking you in the face. And we humans have even fought wars over rights to seabird guano, which was used as a form of fertilizer in the late 1800s.
Anyway, that’s the scoop on poop for now. Maybe we’ll revisit this load later on, seeing as how there’s still plenty of content here.
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