My sister in law recently quipped that "Trees are a social construct" and at first I thought she was just being glib but now I can't get that statement out of my head.
And it's not even one creature or even type of creature. Look up rhizobium.
Tbf, as we learn more about our gut microbiomes, it turns out that humans are that way as well. Maybe that's why we have the thoughts in our heads vs. the feelings in our guts... (no that's actually not it at all, except... isn't it though?).
theres also a definition of a what a tree in the sense , its develops wood, many things are tree like, but not trees: such as palms(just overgrown herbs), dracaena( aka cabbage tree, they have something dracenoid thickining.) extinct plants like giant lycophytes and ferns
I thought crab-like animals were all actually pretty closely related to each other, i.e. all crab-like animals are arthropods, which is a less broad category (despite the incredibly huge amount of species in it) than 'all plants that can form a wooden trunk'. Any taxonomists here to confirm/deny?
Or maybe the microorganisms and food sources that life forms are exposed to have more of an effect on how the macroorganisms evolve than is currently talked about, which would explain why so many things in similar environments evolve similar traits.