- I don't study biology so I may get stuff wrong. All of the info in my posts is taken from various online articles. Please do your own research!
- I'm happy to receive & show off your critter observations but I don't do any sort of species ID. If that's what you're looking for, try iNaturalist
- None of the images or footage used on my blog, including the banner and icon, are mine unless stated otherwise
- My posting frequency can be very inconsistent due to fluctuating interests & mental health reasons
- I try my best to tag common phobias but if I miss something please let me know
💡 What I post / My main bio interests (in arbitrary categories):
- Most kinds of invertebrates, including but not limited to:
‣ Insects, especially mantids and beetles
‣ Cnidarians
‣ Crustaceans
‣ Various deep-sea creatures
‣ Molluscs and worms
- Fungi & molds
- Slime molds, lichens, mosses & algae
- Most kinds of microorganisms
- Many kinds of rare plants, such as carnivorous plants and cacti
- Some species of fish, such as sharks and seahorses
- Some amphibian species, mostly frogs
-- In more general terms, I am almost exclusively interested in tropical environments, the deep sea and jungles/rainforests. I love obscure, "weird" looking critters that don't usually get a lot of appreciation. --
💬//
That's all for now but I might edit this post and add more relevant info in the future.
I was going to have a list of all my tags but figured that might be a bit overkill, please let me know what you think.
Thanks for stopping by 🔆
In my last post, I introduced you, the reader, into the wide world of transposons, those little bits of genetic code that move through the genome all on their own. But is there anything these guys can do besides move around? The answer is no, thanks for reading. Okay, yes, of course, do move around, but it’s by their moving around that they can affect so much more.
One of the simplest ways a transposon can ruin a perfectly good day for a cell is by moving into the middle of a gene. Because transposons move seemingly randomly, there’s no reason one couldn’t move into the middle of a gene. The odds of this are fairly small so don’t sweat it too much, most of your genome isn’t functional anyway. And even on the off chance, a vital gene is disrupted with a transposon, that one cell dying won’t really be of much concern to the other trillion cells in your body. But every once in a blue moon a transposon can move into a really important gene, like a tumor suppressor, and that has the potential to cause cancer. According to research from Johns Hopkins we aren’t sure how common kind of event this is, but new research is slowly narrowing down the connection between cancer and transposons.
Thankfully it’s not all bad news, as over the (millions) of years transposons have been co-opted to help us evolve. While making a gene inoperable is a very probable cause, it’s also possible that the gene can be given a new function, after all over 50% of your genome is or once was a transposon and only 2% of your genome codes for proteins.
A transposon in a normal cell, like a skin, bone or liver cell, won’t be passed on and once that cell dies it will be forgotten entirely. But a transposon that has moved in an egg or sperm cell will be remembered, and be part of that organism for as long as it lives. It even has a chance of being passed on. If the transposon moves into a functional gene it can harm the cell, but it can also add a function that gene previously didn’t have. This transposition, if it winds up in a sperm or egg, and if it causes a change in the organism for good or for bad, will continue to be spread as its descendants breed.
Humans are a good example of this. As our brains have evolved more rapidly than any other organism we know of. One study shows that transposon activity almost perfectly coincides with this rapid evolution, implying that transposons may have had an effect on human intelligence. And this transposition must have started in an egg or a sperm cell to be passed on.
If there is any take away from the story of transposons it’s that biology isn’t set in stone. Despite what you may have learned, or maybe in addition to it, biology is messy and very few things are black and white. You have genes that help you, but some act like viruses and can hurt you, but sometimes they can also help you. We still don’t understand the true nature of the beast, but with enough time, luck, and a whole lot of curious folks doing research one day we just might. And if we’re really lucky on that day we’ll find something weirder and more mysterious to study.
Transposons: What Are They? What Do They Do? Do They Do Things? Let's Find Out.
I’ve talked before the research done in my lab here, but I haven’t talked about my personal research interests. My of interest is, yes you read the title, transposons. What are transposons though? Transposons, or transposable elements, are bits of genetic code that is transposable (hence the name). In essence, I, you, and nearly every organism that has ever existed has bits of DNA in them that will jump around at random. One minute you could have DNA in spot A in chromosome 1, and the next day it will be in spot Q in chromosome 12. This is the nature of a transposable element.
Transposons were discovered in the late 40s by Barbara Mcclintock while experimenting with maize with broken chromosomes who had noticed that some leaves had unusual color patterns. She hypothesized that these were due to certain parts of the gene breaking in some cells and being added to other cells during cell division. This turned out to be false after she had observed that parts of chromosomes had switched places. The fact that DNA could move was so groundbreaking that she was largely ignored for 20 years. However, her work was fortunately rediscovered when transposable elements were discovered in bacteria in the late 70s. And in 1983 she won a Nobel prize for Physiology or Medicine, so the waiting game did pay off eventually.
Today we know transposable elements are in nearly every organism, from the lowly starfish to the mighty echidna, and everything else with DNA. Why and how they came to exist is anyone’s guess. It’s possible that one transposon developed in the first organism and spread, or it occurs multiple times separately. We don’t have DNA samples from the dawn of life, which makes answering this question very hard. Another curiosity of the transposon is how similar it operates to a retrovirus. A retrovirus inserts its own DNA to a host cell’s DNA (like a transposon) to trick the host into producing more viruses (also like a transposon).
There are two classes of transposons, aptly named Class I and Class II, and both of these classes has to do with how they ‘jump’. Class I transposons (aka retrotransposons) move by being copied into DNA’s sister molecule, RNA. The RNA, now free from the chromosome, moves around until it is copied back into DNA. Like a bad neighbor, this DNA then takes the liberties of reinserting itself back into the DNA.
Class II transposons (aka DNA transposons) are much more direct. Instead of going through the messy process of being copied and converted multiple times, it just up and leaves the spot in the chromosome it’s located in and then enters a new area. What’s good (for the transposons anyway) is that most of the information needed to move is located within the transposon, meaning that as long as it doesn’t mutate it can keep up this seemingly random nomadic lifestyle.
But mutations do happen, and the transposon needs a very specific pattern to work, so your genome is littered with transposons that no longer work. In fact, 50% of your DNA is composed of “dead” transposons. To keep this in perspective, only 2% of your genome is actually used as a blueprint for your body. Fortunately for you, less than .05% of your genome has active transposons. These active transposons are mostly harmless so you can sleep well tonight, but that doesn’t mean they affect evolution, disease, and mutations, which I’ll go over in next week’s blog.
Gay Animals Part II: Electric Boogaloo, The Science of Gay, and You
Before I start this article off I’d like to lay a disclaimer: The reason behind why people are queer isn’t very well understood, but all science tries to do is understand the “why” of things and passes no judgment, regardless of the cause. If science said the homosexuality was 100% caused by watching too many cartoons (spoilers: it’s probably not) that information makes you no less you and it shouldn’t affect how you feel about yourself. But, as we will see, homosexuality is not only something incredibly prevalent in the animal kingdom, but is as accepted as any other trait an individual can express.
So, with all that being said, this article will deal with homosexuality, genetics, possible environmental factors, and its possible evolutionary benefits in nonhuman animals. Because the human brain is so much more complex than anything we’ve ever seen, and we still don’t know most of its secrets, it’s important to remember that what might be true for rams, penguins, or even our close relatives like bonobos, is not necessarily the case for humans. Nor should we look at other animals in a human-like manner. For instance, it’s entirely likely that gay animal couples pick up the slack for parents who abandoned their children. We can’t and shouldn’t look at them through a human filter, because it would be impossible to tell if they love each other as human couples (hopefully) do, or if their union is purely survival based. Humans might be the only creatures able to feel love, or it might be more prevalent that we are aware. Whatever the answer, it doesn’t matter here. All I will be doing is going over some of the facts that scientists know, and why this would matter to animals in the wild.
So if any of this makes you uncomfortable, then please skip this post. If you feel I’ve offended you somehow then please DM me and I’ll try to amend this the best I can. Otherwise please click the read more below.
Now homosexuality is kind of ambiguous of a term, and many scientists have conflated it with hermaphroditism, so to avoid confusion I am going to define homosexuality in the animal kingdom in two ways.
Same-sex, long-term courtship.
These are same-sex couples that act towards each other as a heterosexual couple would for at least one mating season.
Homosexual intercourse.
This can last for as long as one night of passion, or be a continuous trait in an individual.
I’m also going to consider bisexual animals on the homosexual spectrum.
PART I: The One With the Genes
Arguably one of the most powerful aspects of biology is evolution, and a key principle in evolution is detrimental traits are less likely to get passed down than traits that make it easier to survive and reproduce. So why is it then that homosexuality, a trait that seemingly provides no advantage to reproduction, is so prevalent not only in individuals but throughout the animal kingdom? If we assume that homosexuality is genetic (and there is good cause to believe that) then shouldn’t that gene cease to be passed down?
Most times the answer is yes, but sometimes if a gene benefits a whole population it will continue, even if some individuals are negatively affected by it. According to one study male homosexuality actually persists because of this very reason, not because it benefits the males, but because it benefits the females. According to the authors, homosexuality is more common in lineages with females who have high androphilic tendencies, that is, a high attraction to males. Now in males, this gene will manifest as a what appears to be homosexuality, but in females this heightened androphilia will manifest as an increased sex drive, making up for the male carriers.
This, of course, does not account for female homosexuality. Nor does it take into account possible environmental factors we’ll get into later. But it is important to highlight how evolution and nature look at traits. Under normal circumstances, unless a trait is highly deleterious (deadly to the individual) there won’t be enough pressure to remove it. But are these genes deleterious anyway? We’ve seen that they may play an important role when not being expressed as homosexuality, but it could play an equally as important role in homosexual animals.
PART II: The One With the Homosexual Helper
Animal preference and motivation are not always the same as it is in people. Swans mate for life. But is that because it makes it easier for them to find a mate in the future, or is it because they can feel a complex emotion like love? It’s impossible to say, so it’s impossible to know why animals do a lot of things. “But goddammit we’re going to try”, science said.
Take the humble penguin. In my last post, I wrote about how gay penguins will frequently “adopt” orphaned eggs and raise them as their own performing all of the same functions as a heterosexual couple would. Why then, waste resources raising something that’s not your own child?
According to Darwin, it’s not just individuals who evolve to protect their lineage, but groups that evolve to protect their species. This is largely the basis for theories on why altruism exists and can be applied here as well. Afterall, a homosexual couple is never going to produce a child, and if an egg or a baby is without a parent the option is left to die the population as a whole will have lost a child. But if a couple unable to conceive their own adopts it, then that is a net gain for the population as a whole. Thus, the population that keeps these genes that reciprocate this kind of altruism is more fit to survive than a population that doesn't. And the adoption phenomenon can often be seen in non-homosexual individuals as well, but it demonstrates a good example of how altruistic genes can help a species grow even at the cost of fitness to the individual.
PART III: The One With the Sexual Leverage
Nature is a fickle mistress, and she does not subscribe to one dogma. Sexuality, while predominantly used for creating the next generation, has been appropriated by many species as a form of leverage, bonding, the assertion of dominance, and even used to take the place of an all-out brawl. So it’s no surprise then that homosexual acts are used in a similar fashion. This is also where the motivating factors of homosexuality moves away from a possible genetic or natural cause and towards as more psychological reason. Take, for instance, the bonobo. This species seems to be functionally bisexual, using sexuality for control rather than attraction. In one instance a bonobo might have sex with their opposite gender for the reason most animals would, to make a baby. In the next instance, that same ape might get into a disagreement with an ape of the same gender. These two apes, instead of fighting, will use sex as a way of diffusing and diverting attention from the disagreement. And yet these two acts of sexual intercourse are entirely unrelated, and likely evolved for those specific scenarios.
And this is true in plenty of other animals as well, dogs will mount other dogs regardless of gender to show dominance. Marmots mount other marmots as a form of bonding. Dolphins will have sex with the same gender for fun, and then sex up the opposite gender for reproduction. The common trend it seems is that animals who are more sexually fluid, or bisexual, leverage their sexuality for personal gain, whether it be bonding, pleasure, or something else. While animals who remain uniquely homosexual have a more positive effect on the population’s fitness as a whole.
PART IV: The Scientific Community and Homosexuality: Do They Know Things? What Do They Know? Let’s Find Out.
Finally, I’d like to conclude with some talk about where scientists think homosexuality falls on the nature/nurture spectrum. Studies have shown identical twins are more likely to both be gay than fraternal twins, meaning that sexuality is almost certainly somewhat controlled by genetics, and this, of course, makes sense based on what we’ve seen and I’ve just talked about. Conversely, there are hormonal, as well as environmental, factors that may also contribute to homosexuality.
While most researchers agree that sexuality is innate, something that develops at an early age, possibly before cognition and doesn’t change throughout one’s lifetime, they are still hard pressed to figure out why. While it is unlikely that parenting has any effect on sexuality, parents can still influence sexuality. Several studies have shown that the each child born in a family line has an increased chance of being homosexual. For instance, the 7th son will be more likely to be gay than the 2nd son, etc. This is suggested to be likely due to prenatal hormones, but the exact reason is yet unknown.
And while homosexuality is innate, homophobia is not. In fact, while it’s likely every species has some homosexual members to it, humans are the only species with homophobic members. Much of what we know about homosexuality is stifled by human biases and irrational fears, something we’ll go over in the last part of this series.
CONCLUSION
So why does knowing the cause of homosexuality matter? Well besides intellectual curiosity, something that science is very fond of, it’s important to have facts. Over the past 50 years, we’ve seen huge leaps in rights for minorities, and that is a change that is still happening. As a society, we’re seeing growing pains. Where many embrace the change towards tolerance with opened arms, either because it affects them directly or because they have empathy for their fellow man, many are resistant to change something that they’ve never seen as broken. So it never hurts to have some objective fact reinforcing a new idea, and where better to get that objectivity than science.
I mean, how well could life be going if you’re trapped in Rapture?
It’s better with friends though! Got a few friends from Fort Frolic that aren’t dead, James, Harvey, Cyrus – and you know, that kiddo Jack ain’t half bad if he doesn’t catch you after one of the Little Sisters and you don’t try to kill him!
