#they're really different plants that have really different evolutionary histories

[alyanas-little-hideout]

Sorry for posting notes but it's actually worth mentioning that taxonomy is a predecessor for determining how different creatures are related based on shared physical characteristics but, importantly, doesn't presume evolutionary mechanism in the same way that phylogeny- that is, basing the connections between animals on the percentage of shared genome data- does.

Phylogeny has 0 concern for shared physical characteristics- a hyrax and a whale are more closely related than a whale and a shark, for instance, despite the shared body plan and lifestyles of sharks and whales and the completely unrelated body plans of hyraxes and whales.

Also phylogenetically -fish don't exist as a group -lobe-finned fish encompasses all land animals -sharks and ray-finned fish are more distinct than any land animal is from another -trees don't exist as a group -birds are dinosaurs, which are reptiles, which are amphibians.

and other fun oddities of biology.

which of my household appliances am i most closely related to

[beakers-and-telescopes]

Seeing UV colors is common for butterflies, but in some species, it is a female-only power

So, you may or may not know that many butterflies can actually see in UV light. It is very cool and I'm definitely not jealous that they get extra colors. It's helpful to them because many flowers have UV patterns on them (invisible to us) that let the butterflies know that they're a good source of food. The plants get pollinated and the butterflies get to eat. Everybody wins. This is a simulated version of what butterflies might see when they look at a flower.

Some butterflies, such as the zebra longwing pictured above, only display this trait in females. Because of this, male and female butterflies will tend to visit different types of flowers. But scientists have just recently figured out how this difference came to be, evolutionarily speaking.

Obviously many species have sexually dimorphic traits, some more prominently than others. There are also cases in which one sex develops a trait that is just... less useful than the other, like this case with the UV vision. Almost all butterflies can see in the UV spectrum, so it follows that at some point in the evolutionary line the male zebra longwing butterflies lost that particular ability. There are multiple ways that this sort of thing can happen, and the article covers them briefly, but after sequencing the genome for these butterflies they found that none of those previously seen explanations were the case.

Basically, we already know the gene that causes UV vision in butterflies. It is called the opsin gene. In zebra longtail butterflies, this gene occurs on the chromosome W, which is the female sex chromosome. That means that sometime in history, this gene just jumped from a normal chromosome onto the female-only chromosome, and has locked the male butterflies out of this ability ever since. This is the first time we have seen a gene do a jump like that, and it is pretty cool.

But anyway, appreciate the girlpower of zebra longwing butterflies getting all the UV vision, and take a look at the study! It's free to read, which is really nice to see.

[script-a-world]

Hello! I am building a scifi setting, and in this setting there aren't really any known planets besides Earth that would naturally support life (not human life, anyway), but over hundreds of years humans have terraformed several planets to support life in order to build settlements there, and that has included introducing plants and animals from Earth to those planets (my understanding is that terraforming, at least on this sort of degree, isn't really likely to be practical in real life, but that's something I am willing to handwave and go "it works because i say it works, just trust me bro" on).

Once that is done, the wild animals and wild plants brought over to a terraformed planet generally speaking are never transported from one planet to another again, although domestic animals, plants that are farmed, and humans themselves, might be. And I can see insects and microbes getting inadvertently transported from place to place among different kinds of cargo, since they're small enough to escape notice (I mean, the most venomous spider species in my country is a population of spiders that exists in one natural history museum because there were some accidentally brought over in a shipment of stuff from South America in the 60s or so. I can well see that happening on a planetary scale in a scifi story, too - but anyway)

My question is, if you have a population of animals that's isolated from other populations of the species to that degree, how quickly do you start seeing clear differences in the traits that different populations have? Like I don't expect to have entirely different species yet in a matter of centuries, but if you have a population of, say, roe deer, that would have been entirely isolated from other populations for like five hundred years, could there be differences between that population and other populations that a layman might be able to spot?

Tex: If everything’s on the same planet, it’s going to be difficult to truly isolate an area or population, because it’s going to be affected by the same planetary conditions, such as orbit around the nearest star, the ocean and its environment, etc.

Darwin’s finches, for example, have distinct variations in phenotype despite being effectively the same species (a similar situation for the Galapagos tortoises), which shows that a species’ genotypes can still appear as different physical traits given different environmental stresses.

It’s difficult to tell when evolutionary changes occur, because this depends on not only the species, but the environmental changes, the speed of such changes, and how deeply they impact a species in question. There currently isn’t any research being done on evolutionary characteristics of animals and their niche environments that I know of which has already been occurring for a hundred or more years, as much of our current generation of science is relatively recent given the scope of technological evolution.

Taking a look at the niche environment, how it differs from the originating environment (if this is part of the equation), how the two differ, and what environmental pressures are exerted would be a good start in extrapolating how phenotypic expressions might be altered without delving into the much more complex subject of epigenetic changes.

Utuabzu: Gravity, levels of light, the colour of the star, the length of the year and day and the degree of axial tilt are all going to have to be adapted to, since there's not that much that can be done about them. Organisms that evolved seasonal behaviours are going to lose those after a while on a planet with negligible axial tilt and thus negligible seasons. Organisms on tidally locked planets are going to lose traits dependent on a day-night cycle. Organisms on a high-gravity planet will get stockier, while those on a lower gravity one will get taller and thinner.

Photosynthesis is dependent on the interaction of a photosynthetic pigment with certain wavelengths of light. The dominant photosynthetic pigment on Earth is chlorophyll a, which reflects away the wavelengths we call 'green' and absorbs most of the rest of the visible spectrum. One theory for why it's dominant is that because the sun's emissions peak around the green part of the spectrum, this protects the photosynthetic organism from getting burnt - one point in favour of this is that non-chlorophyll a using photosynthesizers tend to favour shade. But around a different star, or even further out in our own solar system, chlorophyll a might not be ideal, and plants that use other proteins would reflect different spectra of light, and thus appear different colours.

But in terms of evolutionary timescale, it depends on generation length. Things evolve based on mutations that offer some benefit to the offspring of the mutant, leading them to be more successful than their peers and have more offspring in turn, which then are also more successful than their peers without the mutation and thus spread it through the genepool. A civilisation that can terraform planets on a reasonable timescale can almost certainly use genetic engineering as a shortcut to ensure their new biosphere can thrive immediately.

So you have a fair bit of leeway in terms of what you can do with other planets' biospheres. Terraforming on a scale shorter than thousands of years would already take technology well beyond anything we have, so you can handwave a fair bit.

[thebashfulbotanist]

hey i wanted to ask if you are a certified botanist because I would love to ask a few things about how your job is and the road to becoming a botanist. im a teen with dreams of going to collage and getting my degrees for botany. I want to ask how many years of collage did you do? what inspired you to become a botanist? whats you favorite plant? was the years of collage all worth it in the end?

This is a tough ask to answer because there are many different ways to be a botanist! Typically, the starting point is to get a bachelor's degree in biology. If you can, try to find a university with a botany or environmental science program and see if there are any professors with labs that study things you find interesting. For example, you might be interested in the evolutionary history of oak trees, or how people domesticated maize, or how certain plants respond to climate change. Once you've taken a few classes (maybe in your second year) reach out to those professors (and the grad students in their labs!) and see if they're willing to take you on as an undergraduate researcher.

For me, my path is a little unusual because I actually started out studying animal behavior. Although I took a botany class and mycology class in my undergrad, I wasn't sure I wanted to study botany until I was almost ready to graduate. I went on to do a Master of Science in evolutionary biology, focusing on botany. Currently I'm working on my PhD studying both evolution and ecology of bamboos. I have over 9 years of college under my belt now. It'll probably be about 12 years by the time I'm done. I can't say whether it'll all be worth it in the end because I'm not there yet! But so far I really love what I do.

For many jobs, a M.S. degree is what you need. For example, there are positions with government agencies, such as state departments of conservation and natural resources, that utilize botanists to identify and help write management plans for populations of rare plant species, which often don't require a PhD. Botanical gardens are also a great option with an M.S. or even just a bachelor's degree, especially if you go to an institution that has a program in horticulture. Museum and herbarium curatorial positions may also require an M.S., although requirements for a PhD are becoming more common at these institutions. A PhD is of course required for academia and sometimes desirable for other positions, such as those with museums or government agencies.

However, even if you're not a "professional" botanist, you can still do botany. For example, many cities have local native plant societies that you can join to learn more about native plant species and help promote their conservation. Some universities and societies also have "citizen science" or "community science" programs where you can volunteer to help with research projects, too.

As for what inspired me to be a botanist, I've always loved plants, having grown up helping my mom in the garden, and I took an awesome botany class where we went on a number of exciting field trips. I really enjoyed the field work we did (field botany is usually a LOT of hiking, so get yourself some good shoes/boots if you want to do it!) and was excited to learn more. Plus, I really enjoy learning about WHY plants are the way they are - how their environments shaped their evolution.

I don't really have a favorite plant - there are so many! But if I HAD to pick one, I'd probably say the Pacific Dogwood, Cornus nuttallii. Don't tell my bamboos!

[aerodactylheresies]

Yeah literally the biggest factor in insects (SPECIFICALLY INSECTS) getting big was that there weren't any aerial vertebrate to compete with. The largest insects are actually from the Permian, not the Carboniferous, and some of our modern insects are actually pretty comparable in size to some of the "giant" insects of the Carboniferous - which themselves were outlier among many, many average sized arthropods. In fact, most groups of arthropods that lived during that period don't show any gigantism at all! You've probably heard the fact that the largest animal ever is alive today (the blue whale), but did you know we also have the largest spider known alive today? The goliath bird eater is bigger than any known fossil spiders! Plenty of other groups peaked in size at various points in time, few of them when you might expect.

For arthropods in general, high oxygen might have played some role, but it's no longer considered the end-all-be-all reason for gigantism.

Here's a fairly recent article on the topic that I think summarizes the general consensus pretty well: https://cedar.wwu.edu/wwu_honors/373/

Arthropleura (not an insect, but a millipede) stands alone as the spiders georg of terrestrial arthropod gigantism. At nearly 3 meters long, it's the only true Carboniferous giant in my mind. Really, they're an outlier and whatever was going on with them must have been totally unique to their evolutionary history. It was almost certainly for a different reason than the "kinda big" insects. The answer may simply be that nothing had really evolved to be a decomposer yet, and vertebrate herbivores were sparse, allowing millipedes to get really *really* good at just shoveling ridiculous amounts of plant matter into their mouth.

guys literally every study has indicated that high oxygen content does NOT lead to larger animals plz stop spreading that one thanks

[script-a-world]

Submitted via Google Form:

I'm trying to design an alien species that is categorised as both plant and animal. Is that possible? Or only if defined to how we define plant and animal? In that case how could aliens define them differently?

I'm suppose you may already be thinking of stuff people create that do seem to be both plant and animal. Like those carnivorous plants with whip like vines that can seize prey - but they're considered plants and not an animal. Then there are ents in Tolkien's work. But those are still animals that resemble trees, not considered plants. Not what I'm looking for.

Miri: Scientifically, we differentiate plant vs animal at a cellular level: plant cells do not have a cell wall, animal cells do. That’s just the start of the differences, which are mostly contradictory enough that they could not exist in the same being. A table of differences can be found at https://www.toppr.com/guides/biology/difference-between/plants-and-animals/ (and more information is available at many sites with a quick “plant vs animal” google search as this is a topic that was covered in many high school biology classes in North America when I was in school - I have fond memories of doing stains of plant cells to look at under the microscope.).

Aliens may not even have the same concepts of “plant” and “animal”. We haven’t met any (so far as we’ve been publicly told) so it’s all up to imagination. This may be a case of Aunt Scripty’s Rule of Reality - you break it, you bought it. Consider if it’s something you really need to define that accurately. If they think it’s a plant or think it’s an animal, does it matter to your plot if it really is? Is anyone pulling out the microscopes to check? If they are, then it’s worth making those distinctions in your story and building what it means in your world. If it doesn’t matter to the plot, and it’s never going to come up, this may be a bit of world building you can keep behind the curtain.

Feral: Plants and animals are not even the only defined categories of life in our world. You seem to be drawing your categorization of life from Linnaean taxonomy, which is not a particularly helpful classification system as it was developed in 1735, aka before Darwin proposed the theory of evolution. If you look at other taxonomic ranking systems, like Whittaker’s 1969 Five Kingdoms or Woese’s 1977 Six Kingdoms, you might find more inspiration for how the domains of life may be divided and categorized. And increasingly, it’s being accepted that it’s not just humans or even non-human animals, but plants can have a form of intelligence, and possibly anything or everything else could experience consciousness.

Utuabzu: sounds like you're describing fungi, archea and bacteria, none of which are plants or animals but are most certainly alive. Fungi have been observed to transmit electrical signals across their mycelia and to react to stimulus, which may indicate some level of awareness (if they think or feel, it's in a way that's pretty alien to us). Lichens are even weirder, being composite organisms made of various combos of fungus, bacteria and plants, and also being some of the oldest land organisms and the sturdiest (lichens are the only plant-like-things growing on Antarctica, and the ISS has had problems with lichens on its outer hull).

Plenty of plants react to each other and their environment and plant cognition is a legitimate field of study within botany, so plants that move and act more like animals are perfectly possible. But honestly, if you're working with aliens, there's no need to fit things neatly into the taxonomic categories we're used to. They're alien organisms, they'll have (presumably) had an entirely separate evolutionary history and fall into their own categories. You can have human characters refer to things as plants and animals, and then have another character correct them if you want.

For worldbuilding purposes your most important concern is going to be the difference between autotrophes (organisms that create their own food through photosynthesis or chemosynthesis) and heterotrophes (organisms that must acquire energy from other organisms, generally by eating them). Autotrophes tend to be more sessile (unable to move) because motility (the ability to move) requires energy and specialised structures that don't necessarily make sense for something that just needs a source of light energy or chemical energy and nutrients. Heterotrophes do tend to be motile because they have to find food, but there are plenty of sessile heterotrophes. Most corals, sponges, and fungi either rely on water currents to bring them food, or grow outwards to find more food and are able to reproduce and spread out in sufficient volume that it doesn't really matter that their food will run out. Remember, evolution doesn't prefer the “best” lifeforms, just the ones that continue to successfully reproduce.