The definition of what constitutes a species is a human construct.
Two bird populations living in the same locale but divided by a mountain range therefore not naturally breeding with each other would classify as a different species, even if they could breed with each other.
Seems to me, that we divide other animals based on some of the most minor of phenotypic expressions. The slight coloration of a bird’s crest, shape of some lizard’s nose.
Yet with Homo sapiens we seem to be allergic to the idea that our drastic swings in physical attributes could possibly qualify as a different species (we obviously call them “races”). But they plainly diverged from each other due to geographic and reproductive isolation and adaptation to environments. Which is precisely what causes species to diverge into new ones.
Are we supposed to pretend that Africans DONT have black skin due an adaptation to their environment?
Do other animals get divided into races? I know dogs have “breeds” and we don’t consider those species. But I don’t hear about “races” in other animals.
> Seems to me, that we divide other animals based on some of the most minor of phenotypic expressions
It might seem like that to you, but you'd be wrong. Taxonomy prioritizes genetic distance and reproductive isolation over superficial visual traits that humans happen to find striking. While phenotypic variations like skin color or facial structure are highly visible, they represent a microscopic fraction of the overall genome and do not indicate the deep divergence required to define a new species.
And from a genetic standpoint, Homo sapiens is remarkably homogeneous. Two humans from opposite sides of the planet are generally more genetically similar to each other than two chimpanzees from the same patch of forest. Traits like skin color (an adaptation for UV protection) or nose shape (an adaptation for humidity/temperature) are rapid evolutionary adjustments. They change quickly on an evolutionary timescale without requiring a fundamental split in the species' lineage.
In contrast to other animals, because humans never stopped breeding with one another, we never had the chance to "drift" far enough apart to become different species. Geographic distance in humans has historically acted as a filter, not a wall.
So there's your answer. Because of this unique genetic homogeneity (and not because of some imagined woke censorship), speaking of human subspecies would be scientifically mistaken.
> The definition of what constitutes a species is a human construct
That makes it sound like the boundaries between species are arbitrary, but they are not. Sure, there are corner cases where things become debatable, but those are the rare exceptions, not the rule.
> Two bird populations living in the same locale but divided by a mountain range therefore not naturally breeding with each other would classify as a different species, even if they could breed with each other.
This is only the case if the separation has been there long enough for the two groups to develop distinct genetic markers or physical traits (like the beak shape or plumage mentioned in the original comment). The deeper reason they are classified as different species it that they are de-facto on different evolutionary trajectories. Which doesn't happen for human populations because historically, whatever obstacle divide us, we find a way to get around it.
> Two bird populations living in the same locale but divided by a mountain range therefore not naturally breeding with each other would classify as a different species, even if they could breed with each other.
Really? I thought the requirements for species classification were: (1) must be able to reproduce and (2) offspring must be fertile.
There are a lot of subtleties. Ring species are a particularly fun one: you can have a population that live around some natural obstacle (like a large body of water) where individuals can breed successfully with individuals near to them but not with ones further way (like directly across the barrier), in a continuum of variation.
Thought experiment. Three populations, A, B, and C, divided geographically along a line. Individuals from group A can breed successfully with those from B but not with those from C. Individuals from group C can breed successfully with those from B but not A.
How many species are there? This is why the term "species" can never be entirely objective. I remember the eureka moment I had when I finally understood this (admittedly somewhat simple) point.
It can even be more subtle, it's entirely possible that some rare members of A can C breed, and some members of C and B would not be able to breed. The "fertility" relation can only be decided between two individuals, not groups. Group-level fertility is a statistical average of individual fertility.
That said, I don't think that means that "species" is entirely subjective or meaningless.
the reproductive incompatability, is based on physiological range.
in general, there are multi organizational levels of reproductive incompatability.
in this case, the geographic distance, orogenic blockade, and ecological confounds of arctic conditions preclude easy mingling of U.arctos x U. maritimus.
Sometimes it’s hard to objectively tell whether two animals don’t appear to reproduce because they are unable genetically, or technically able still but behaviorally unwilling in normal natural circumstances, or we don’t know but we just haven’t observed it for that particular combo, etc
my understanding of what classifies something as being a part of the same species is the fact that they can make children that are viable to have children themselves
horses and donkeys can breed to make mules, but the mules usually cant reproduce, this is the same with tigons and ligers but sometimes the females are viable
so if they can produce children that can produce children, they're the same species. where this line is blurred, so is the species line. geographical barriers have nothing to do with it.
if you consider that geographic barrier is an environment of immediate lethality, or infecundity, that is physiological incompatability, and would be a speciation.
if you consider that geographic barrier, simply precludes, interaction between individuals, then you will have founder effect, thus one population will be genetically decended from a sample of the larger population.
> my understanding of what classifies something as being a part of the same species is the fact that they can make children that are viable to have children themselves
things are a bit more complicated than that, because having fertile offspring is not a transitive property.
Ring species: population A can mate with B, B with C, C with D, and D with E, but A and E cannot mate, even though they are part of the same continuous chain.
Ensatina eschscholtzii salamanders in California exhibit this non-transitive behavior. Populations at the ends of the coastal ranges can interbreed with their neighboring populations, but where they meet in the south, the "ends" of the ring do not interbreed.
I much prefer the Napolean attributed joke version where diligent is replaced with energetic. It ends with Napolean being asked "but general what about the fourth group, stupid and energetic?"
Optics. One can argue that Red Hat was working with DoD on just security. But after this white paper on how to better kill people, that facade has fallen over.
Yes, it is fairly common with some plastics. better plastics won't but there are a lot of different plastics with differt formulas (and many can be mixed)
I don't agree with both of the above analogies. Sometimes you must go in depth on a single paper, while other times it's broad research that's required. Different tools and methods for different tasks.
What your describing here
> reading the portions of those papers that you are interested in
Is a hybrid use of the technology which no one would argue against.
The question remains if students have the foresight to use the correct method and which results in the best learning outcomes.
For myself, I would have absolutely let LLMs summarise swaths of text and write my essays when I was at Uni. That's just me though. Maybe today's learners are better than I.
The author did not outright suggest the banning of all technology. They even linked to a digital typewriter. After the very paragraph you quote, they suggest instead to offer a more human centric approach to helping disabled people. It's not a huge leap to suggest that your sister could continue to learn with the above two solutions; a disability tutor combined with a OLED screen.
The Nintendo DS fit in your pocket but it didn't hearld in mainstream gaming.
Gaming went mainstream because it went mainstream. Technogy improved, it became easy to setup and play (unlike a computer at the time), competition was high between Sony and MS which resulted in quick generational leaps. And finally, all the gamers grew up inviting more gamers to be gamers.
Once it became big money, gaming attracted attention propelling it further.
Like any technology, it's a combination of things that leads to high uptake.
My opinion is that VR will go mainstream when it becomes afford, useful and easy to use. IMO we are years away from good useful VR.
Two bird populations living in the same locale but divided by a mountain range therefore not naturally breeding with each other would classify as a different species, even if they could breed with each other.
So your question is hard to answer.
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