There's no such thing as a tree (phylogenetically) (2021) (opens in new tab)

But "there's no such thing as a fish" is a different statement than "there's no such thing as a man". First off, "man" is not a biological category, but a human social category. Biologically, "boy" and "man" are both "male". And there is such a thing as male in biology.

There is such thing as a fish, just not phylogenetically: all the different organisms that we think of as fish don’t form a group that includes all the descendents of all fish and all fish. Why is that? Some things we consider fish today have common ancestors that have legs, i.e. not fish.

https://evolution.berkeley.edu/fisheye-view-tree-of-life/wha...

Fish only exist in a duck-typing sense, not in an unambiguous ancestry tree sense.

Being a fish is better seen as an interface rather than an inheritance.

Which is how cyborg feminism sees those human categories, too.

You lost it a bit at the end with women and men. Those aren't phylogenic groups, so not even closely related to the concept. It's a bit like saying "there's no such thing as granite" because not all granite is the product of two other pieces of granite having sex.

There is such thing as a men and women. Gender has nothing to do with biology!

Or perhaps phylogenetics does not determine what categories are relevant.

All fish are not phylogenetically correlated:

Things became fish multiple times independently.

There is no "first fish from which all fish derived".

Phylogenetic existence refers to the evolutionary history and relationships of a species as represented in a phylogenetic tree. This tree is a diagram that depicts the lines of evolutionary descent of different species, organisms, or genes from a common ancestor.

So monkeys are phylogenetically related, because all monkeys that we know have common ancestors.

Fish came to be multiple times independently. Being a fish, a tree, or a crab is a strategy, not a species.

Which is ironic because we call it the "tree of life", but it should be "forest of life" (but since life originated in the sea, it should be the "sea of life"), since trees don't have a single phylogenetic root: There wasn't a "first tree that all trees descend from": Things became trees independent of one another, because being treelike is beneficial early on, much like being fishlike and crablike.

Cladistically you can decide:

a) There are fish. Sharks are fish. Trout are fish. So therefore humans are fish as we are more related to trout than we are to sharks. This is basically saying that "fish" is roughly the same as "any vertebrate" or "any vertebrate with teeth" (depending on where you draw the line).

or

b) There is no such thing as a fish. There are THREE things: sharks/rays, ray finned fishes, and lobed finned fishes (which includes humans)

That's the joke in the name of the British show.

It says in the wikipedia article that the quote comes from the show.

Edit: Removed.

I would delete but I can't, because there's a reply now.

Biology is fundamentally based on evolution, so when viewed through a biological lens, a classification based on evolution is appropriate.

We know of course that taxonomy is only one way to group organisms. People use plenty of others, including ones more beneficial to the human experience.

We group plants by the hardiness zones they can tolerate, for example. If you go to a plant shop they'll likely have plants which thrive best in sun outside, while others which need shade are inside or covered.

A zoo might group animals by where they are found, with zebras, ostriches, elephants, and giraffes together in the savanna section, rather than place all of the mammals together and the birds elsewhere.

As others already mentioned, "fruits" and "vegetables" are culinary definitions, not biological ones. Far more people use the culinary term "vegetable" to describe a tomato than the botanical term "fruit".

We also have religious classifications, like the Biblical prohibition: "“Nevertheless, these ye shall not eat of them that chew the cud, or of them that divide the cloven hoof: as the camel, and the hare, and the coney: for they chew the cud, but divide not the hoof; therefore they are unclean unto you.”

You've got that exactly backwards. Humans say "fish" and "tree". That's the entire point of the article.

Ehhhh I strongly disagree with your statement.

The biological system of taxonomy is really for the biology of the organism. We have other categories we use (as humans who are not biologists), even though we borrow organizational structure from biologists! For example, the conceptual category of "vegetable" is a culinary term, not a biological one, and is a good example of a category not used by biologists.

There's a common saying, "Knowledge is knowing a tomato is a fruit. Wisdom is not putting it into a fruit salad". I believe that biologists should be categorizing organisms based on their origin, but people who are not biologists should not be bound by categories created by biologists.

For example, palm trees and bamboos are not trees biologically, but actually tall grass. The biological category of "tree" may not apply, but when you hire a landscraper, you aren't using the biological category of "tree", but rather the gardening category of "tree" (when you need a palm tree cut down). That's not a failure of biology, that's just because we use 1 word "tree" to describe 2 categories used by different fields.

Since an organism characteristics depend a lot on its evolutionary history, classifying organisms like that helps us make predictions and assumptions based on our knowledge of related organisms, so it's quite beneficial to humans. Also, the other classifications like tree, shrub, fruit, whatever, are also valid and used in biology, just not the main classification system. The other feature of phylogenetically classifying organisms is that it's valid for all life, which is a nice property.

No you don't.

Lots of plants have leaves. A few don't, some primitive because they hadn't evolved them yet (e.g. algae) and a few because they lost them (broom, cacti). If there were no trees and nobody had ever seen a tree you could still explain leaves.

Lots of plants have wood. Things that aren't trees have wood. They're called bushes. Wood is a thing separate from trees. Not all trees have wood: bananas grow on really big herbs that people call trees because they are tree-sized, but they're herbs. Palm trees aren't really made of wood.

> You need to invoke tree to define leaves and wood.

I don't think so?

All non-tree plants have leaves (almost all maybe? edit: not cacti, so not all but most). Wood can be defined biologically ("cellulose fibers embedded in a lignin matrix" or something like that)

True but the wrong point here.

Lots of different and only loosely related types of plant have evolved to be tall with thick strong stems to get above other plants and capture the light.

That is a way of growing, and we call it a tree, but the point here is not "trees do not exist" but "lots of totally different unrelated types of plant came up with being tree-shaped independently."