A question for those that know about biology/evolution

[Potoooooooo]

I was looking at the future is wild

and it got me thinking about future evolution&Taxonomic rank

and I wondered how different would an animal have to be, to be considered a new class seperate from mammals,birds,etc

 

[ApostateAbe]

The way I see it, the current taxonomic structure will start to have problems in the evolutionary future, because evolution happens through speciation, and speciation happens when a single species splits into many. If we were to go back in time to the beginning of mammals, the Class Mammalia would be misleading as a "class." It would be just a single species. Same with the Kingdom Animalia, and same with every branch on the family tree, big or small. What happens millions of years from now when Homo sapiens populates the whole Milky Way Galaxy and diverges into THOUSANDS of new and different species? Phylogenetically, we would have to fit them ALL into the taxon Homo sapiens. It may mean we will need to change the word of the rank "Species" or redefine "Species."

 

[Valjean]

This Linnaean system of categories was developed almost three centuries ago, before people even realized that it roughly corresponded to different degrees of biologic relatedness. This idea was tacked on only after the theory of evolution became the fundamental organizing principle of biology.

The categories were always educated guesses and, even though we now know life to be a continuum rather than a series of ranked steps, and have graduated to a cladistic system, the Linnaean system is just so amazingly useful and intuitive that it's still used, informally, as a convenience.

So, to answer the question, it's an educated guess, an arbitrary line in a continuum representing some distinctive, overriding characteristic of a group, leaving transitional forms for biologists to argue over at cocktail parties.

https://en.wikipedia.org/wiki/Cladistics

 

[fromderinside]

Humans have given rise to information as a determining factor. Look for such to be a part of future classifications, say, in about 10k years.

 

[Valjean]

Humans have given rise to information as a determining factor. Look for such to be a part of future classifications, say, in about 10k years.

?????

 

[Underseer]

I was looking at the future is wild

and it got me thinking about future evolution&Taxonomic rank

and I wondered how different would an animal have to be, to be considered a new class seperate from mammals,birds,etc

You don't know the answer to this question, therefore this proves that science is wrong, therefore it also proves that the universe was farted out of the butt of a giant space goat! I read it in a Special Book! [/theist]

 

[Peez]

Potoooooooo:
I was looking at the future is wild... and I wondered how different would an animal have to be, to be considered a new class seperate from mammals,birds,etc

The short answer is: 'it depends.' There is no uniform amount of difference that is used to determine domains, kingdoms, phyla, classes, orders, families, genera, or even species (to say nothing of superclasses, subphyla, etc.). How does one decide whether the difference between a nematode and an annelid is greater than the difference between a sea star and a walrus? In fact biologists do not typically think in terms of these taxonomic ranks, except in the most general way and within specific groups. Rather we think in terms of phylogenies, which tend to correlate loosely with taxonomic classifications.

Chronospecies raise another issue: if one species evolves into two others, and those evolve into four more, and the four evolve into eight brand new species, how do we sort out species and genera and families across this time? The short answer is that we don't. Again, the taxonomic levels are largely arbitrary, imposed for convenience on the living world. When it ceases being convenient it is easily abandoned. Note that if mammals evolved from species Mammalia mammalia, then M. mammalia was still a species, we don't start referring to it as a class (even though it was the ancestor of a class).

Peez

 

[untermensche]

I wondered how different would an animal have to be, to be considered a new class seperate from mammals,birds,etc

Too different for any human to see in a lifetime. Or a thousand lifetimes. Or the entire history of humans on this planet.

The most you could hope to see is a new species. And you know a new species based on reproductive success. If it can reproduce with itself and not with anything else.

 

[Peez]

untermensche:
The most you could hope to see is a new species. And you know a new species based on reproductive success. If it can reproduce with itself and not with anything else.

Except when it can.
:devil-smiley-029:
Peez