#evolutionarybiology

[srlgemstone]

Potamon sp. Crab Fossil; Pleistocene Epoch (2.58 - 0.012 MYA)

[autism-freaks]

I think it's a common misconception that domesticating animals is somewhat like enslaving them. It really is more of a symbiotic relationship. No wild animal would have willingly put up with early humans if they didn't get something out of it. Wolves wouldn't have stayed with us and become dogs if they weren't getting food and safety out of it. Many large herbivores that are now domesticated could and would have easily trampled their early human captors or broken their enclosures open if they didn't have a reason to stay. Sometimes individual animals still do if we don't give them what they need.

The animals that have stayed with us for thousands of years have evolved to cooperate with us better. Dogs have additional facial muscles around their eyes that wolves lack in order to mimic human facial expressions. Sheep grow their wool perpetually while their wild counterparts don't because a bigger fleece means they're more likely to be allowed to breed and be kept around. Domestic dairy cows produce much more milk than wild bovine species and domestic hens lay more eggs. Do you know how energy costly producing eggs or milk is for an animal? It's pretty intense! They wouldn't be able to do that if we hadn't given them the food and safety from predators and the elements to.

And we really need to show these animals respect and gratitude for what they give us by taking excellent care of them. They gave up a lot to be with us, often including the means to take care of themselves in the wild. That's a huge reason why I'm not against using animal products, but I hate factory farming. They are still living, breathing creatures with needs and feelings. They deserve a comfortable life and, when the time comes, a humane death.

[da-real-god]

[pathetic-gamer]

‼️fun game alert‼️

guess the mystery animal by guessing animals and seeing how closely related they are!

[monarchbutt]

what if we kissed at the mazon creek fossil beds 😳

[hbakroun-blog]

Click here for help

[ramblingsfromthytruly]

wish i was immortal because i want to learn about neuroscience, astronomy, psychology, philosophy, evolution, microbiology, history, mythology of different cultures and much more while also acquiring more and more languages and reading books from all around the world from all times and make art and people watch from a cozy lil window nook with a cup of coffee warming my hands

well i'm not immortal so i'll make it my life's mission to do as much of this as possible, my life is to be full of constant learning <3

realizing i make quite a few posts like this but eh

[semponant]

Absolutely love this guys channel, here are the videos I recommend if you are interested in evolution by any chance

[bookmothic-dyke]

Taxonomically we’re all just really really fucked up fish.

Who then went and invented capitalism.

Not worth.

[angelatticus]

Thinking about birds, again. The dinosaurs that didnt die. Whose teeth formed beaks and whose screams formed songs. Innocuous and yet they are living proof of millions of years worth of history and evolution. How can you deny them, when here they are, singing their survival upon your windowsill?

[replicantapologist]

How do phylogeny and taxonomy relate to each other?

I'm writing this because phylogeny is a very dear concept to me, and I hate seeing it being misunderstood. And because @glitter-stained asked me to elaborate on a vague post lol.

(and then I turned it into sort of an exercise too).

Now, I know that this is super super niche, and that for 99.99% percent of the people, it doesn't matter. Anyway, I saw a post which implied that phylogeny and taxonomy are concepts which are opposite to each other, or that using one excludes using the other, and that's not at all how things are.

So, what are taxonomy and phylogeny?

Taxonomy

We love putting things in neat little boxes and classifying them, saying this is a fish and this is a dog and so on. If I asked you to think of a fish and of a canine, you'd think of two very beings. Right?

Taxonomy is the science of creating those boxes. Then we put the things that are similar in the same box (which would be classification, but the two parts of this task are intertwined, of course). I guess 😬.

You may be familiar with Linnaeus' classification, with its hierarchical categories of Kingdom, Phylum, Class, Order, Family, Genus, Species.

Linnaeus' system had three kingdoms - plants, animals and minerals.

The taxonomy system we use nowadays is based on Linnaeus', but with some changes. For example, we don't use kingdom anymore (the broader hierarchical category being the three domains: Bacteria, Archaea and Eukarya (everything that isn't bacteria or Archaea, basically)). Of course, we only classify living beings.

There is a method to that creation of boxes and deciding in which box to put something.

Linnaeus, for example, grouped organisms by their physical traits. That led to boxes that don't make sense anymore nowadays. For example, Linnaeus put Fungi in the plant kingdom. I guess that, looking at the visual of plants and fungi, that would make sense...

But wait, why does it not make sense to put Fungi and plants together anymore?

Well, that's because nowadays we believe that the most correct way of grouping organisms is by reflecting their inferred evolutionary relationships.

And how do we do that? By constructing phylogenetic trees!

Phylogeny

A phylogeny is a hypothesis of evolutionary relationships between organisms of different species.

These guys here:

Getting into the details of how to make phylogenies is extremely outside the scope of this post (and is a hot topic in Biology. People have gone to war because of this. Rivalries were born because of this. Academic insults were exchanged because of this). Basically, we collect data about organisms (used to be morphology, now we are in the era of molecular phylogenies, but this also is a hot topic) and use models to determine how the changes of certain features reflects their evolutionary relationships.

An important concept, however, is that of monophyly.

A monophyletic group is a group of lineages which comprise their ancestor and *all its descendants*.

Using that image above, for example:

B and C form a monophyletic group, which well call BC. Because it includes the ancestor (the node) and all of its descendants (in this case, species B and C).

Now, A and B don't form a monophyletic group, because this group doesn't include all the ancestor and all of its ancestors (C is left out). The group AB is what we call a paraphiletic group.

And I'm saying this because sometimes, we used in the past a phylogeny that we have now determined to not best reflect the evolutionary relationships anymore. For example, in school I learned about the group "Bryophytes" which is useful when were studying similar plants, but that does not include a group comprising an ancestor and all its descendants. "Bryophytes" is a paraphiletic group.

Why am I talking about that?

Well, because inferring monophylies is of one of the goals in the construction of phylogenetic trees. Sometimes we can't determine that, sometimes we have different hypotheses for how to resolve the tree (yeah, war, rivalries and academic insults too), but we want to solve that. In the ideal world, we'll have a tree only with monophyletic groups, and that is what will allow us to... CLASSIFY THINGS.

And that's how we reconcile taxonomy and phylogeny.

Taxonomy and phylogeny are friends! Or, they should be. Then again, this is perhaps a good moment to say that I am veeeeery Dobzhansky biased, and I take his "Nothing in Biology makes sense except in the light of evolution" words to heart. But so does Biology in general nowadays. Modern taxonomy is phylogeny based.

In the platonic world, we have all monophyletic groups resolved (always keeping in mind that these trees are *hypotheses*, and that we can always find ones that better describe the evolutionary relationships).

Look at this beautiful phylogeny of flowering plants (angiosperms) by level of order:

Now, I not only mentioned fishs and dogs above because they were random examples hehe.

You see, this arbitrary thing of creating boxes leads us to funny situations where the technical term for a thing doesn't correspond to the popular one. If you are pedantic enough. And funny 👍.

Case in point: Sarcopterygii.

If you look at Wikipedia, this group will be defined as follows:

Sounds very much like a fish, doesn't it?

But let's take a look at the phylogeny of Sarcopteriigy:

Look who's there in the right corner...

Tetrapoda! (Which comprises amphibians, birds and mammals). Which includes dogs.

So...

This entire post, just to say that I, typing this post, and you, a human reading this post, and a dog, are fish! This is what happens when we put thing into boxes 🤷‍♀️.

This is the (more) niche version of the "Dinosaurs are still alive because the avian dinosaurs are birds, only non-avian dinosaurs are extinct" joke. (The technical basis in the same: monophyly).

This one:

Anyway. Thanks for coming to my TED talk!

Anyone who made it this far, feel free to ask any questions and/or complement and/or correct anything 🥰

[disgustedorite]

Been working on recording evolution games and their history on fanlore. Do you have any idea how deep it goes. It might go even deeper than we can ever know. a

[factual-flittermouse]

Ducks seem like peak evolution to me. Bit of a weird take, maybe, but think about it - they can fly to migrate, swim and float with their webbed feet, and walk (waddle) to nest on land or in trees. The only thing they might be missing is self defense, but I guess that’d make geese the superior species…

[da-real-god]

[isopodiclopedia]

We out here really not moving around like these absolute elites of evolution.

‘Anostraca’ is one of the four orders of crustaceans in the class Branchiopoda; with members being referred to as ‘Fairy Shrimp’.

Video: @pico-cosmos

[monarchbutt]

hey