"Georgina Mace has devoted her Life Scientific to trying to limit the damage to our planet's bio-diversity from this alarming loss. For ten years she worked on the Red List of Threatened Species, developing a robust set of scientific criteria for assessing the threat of extinction facing every species on the planet. When the list was first published, she expected resistance from big business; but not the vicious negative reaction she received from many wildlife NGOS. Her careful quantitative analysis revealed that charismatic animals, like the panda and the polar bear, are not necessarily the most at risk."

http://www.bbc.co.uk/programmes/b07jys1h

  Food - human

 Local : check 

  Sport hunting/specimen collecting

 Local : check

   0. Root -> 6. Rocky areas (eg. inland cliffs, mountain peaks)  
    Suitability: Marginal 

This sort of "breaks the fourth wall" for me, using national boundaries defined by human culture/civilization in a biological definition of humans.

Id say global nuclear war is a very real and very tangible threat to humans and many other species around.

Which in a strange way makes that that statement correct: that threat is not unique to humans. Many earth species share the Anthropocene, meteorites etc. as extinction threats. That being said, it would be nice if the website had a list of universal extinction threats - mostly to send a message.

Also distorting our sense of danger is our moral psychology. No one has ever recruited activists to a cause by announcing that things are getting better, and bearers of good news are often advised to keep their mouths shut lest they lull people into complacency. Also, a large swath of our intellectual culture is loath to admit that there could be anything good about civilization, modernity, and Western society.

It seems he was right in this instances as well, as evidenced by the down votes being applied to your comment.

Actually, everything, at least in my local area, is pretty good. There's no food shortage, we have medicine and vaccines, I voted recently and, at the polling booths, there was no one with guns telling me where to mark the ballot paper. The employment rate is pretty good. I feel safe and secure in my home and on the street.

What is it with everyone trying to scare the crap out me everywhere I turn.

Sure, things could be better, but I don't recall the last time the marauding hoards of barbarians came through and took all the women and children and burned all the crops, so can we all just relax for a moment? We might get along better that way.

We're a pretty persistent pest, we've even learned to write things like "Deliberate concentration and inhalation of contents of can may prove harmful or fatal" on the back of cans of fly spray - that's pretty impressive for a species who posses The Bomb.

We'll make it through these troubling times, just like we've made it through the past, what? 40,000 years?

Just chill the <expletive deleted> out.

I remember the marauding hordes, genocide has occurred in your lifetime. Just not to you.

To be taken seriously any thought of our species has to consider the whole world and several hundred years of history and future.

*Conditions apply, nothing is free

And "nothing is free" is a stupid belief. Lots of things are free. Pretty much everything that matters IS free.

This happened very recently to the Yazidi people, but maybe it didn't happen to you. The only difference is they killed all the men too.

Pragmatist: let's fix these problems.

There's a big difference between solving problems (which means communicating about them) and getting upset with problems. Changing the world for the better is inspiring, not depressing. Whether you get upset with the message is a choice that you have made.

FTFY

"Everything is peachy" is just wishful thinking.

Everything IS peachy. Fixing problems is the opposite of what life is about. It's fine as a hobby, albeit a rather dull one (I can think of a thousand other things I'd rather be doing, but hey, whatever rings your bells).

In purely hypothetical terms imagine that within 30 years climate change becomes severe enough that it unavoidably affects my life. For example sake, let's assume that I live in Dubai and Dubai becomes uninhabitable[1]. This would limit me on a daily basis and I wouldn't be able to do the things that I want to do.

If that's not your concern, that's perfectly fine. It's also perfectly fine that I discuss these problems with other people who care about them. If you don't care about this discussion it's always trivial to ignore it.

[1]: https://www.theguardian.com/environment/2015/oct/26/extreme-...

That should only happen when things are actually "just peachy". It might be a while before then. Several years at least.

I'm not saying the science is wrong, just that there's a constant thread throughout human history of worrying about it.

Global nuclear warfare would've happened by now if it wasn't for both the fear of mutually assured destruction and global nuclear conventions, I think. And sheer luck.

And preparing for an extinction-event sized asteroid isn't a bad idea either; the chances of it occurring in our lifetime is small, but the chances of it occurring again is 100%. The chances of people being able to detect it early enough and do something about it are actually pretty high, in part due to the fear of it happening again. Detection could still be better, of course.

More like pure survivor bias on your part!

An event that kills all humans in one continent would be horrible but would not present "a threat to humans" in the meaning of species survival/preservation.

An event that kills 90% of people worldwide would be horrible but again, would not present a threat to species survival, the humans were just as dominant in 1700s with less than a billion of us than we are now with 7.4 billion.

Global warming can really hurt hundreds of millions of people, but it doesn't have the potential to be an extinction event, you need far more serious threats for that.

Speaking of which, wasn't there some kind of massive reduction of the homo sapiens population at two point in time ? I seem to recall a documentary with a few scattered tribes walking in the blizzard. Something like ony 10 000 humans left.

My view is that a nuclear exchange is very unlikely, and the likelihood of an exchange of global proportions practically nil.

Which two or more of the 9 known (or suspected) countries with nuclear weapons would participate in this global war?

[0] http://www.scientificamerican.com/article/local-nuclear-war/

If USA and USSR at height of paranoia and hatred can't get it together to kill us all, I doubt they ever will.

The fact remains that even a misinterpreted signal has not lead to the trigger of retaliation.

I'd even go as far to say that nuclear weapons have never been used in an act of aggression in a time of war. The war was already over when the US blew up Hiroshima and Nagasaki, what the US did was just ass-hattery.

But if you find it helps your moral psychology to worry about it, by all means, go right ahead. I'm going to continue to feel more concerned about being involved in a motor vehicle accident, if you don't mind.

The Japanese were closer to collapse than we realized, but if the invasion had started, neither side could have prevented major losses, even if both side's leadership would have preferred to. And we were days away. The war had a momentum of its own.

It's true that a misinterpreted signal has not led to retaliation... so far. We've been quite lucky. If Vasili Arkhipov had been a little more cranky on October 27, he could easily have been convinced to agree to launching a nuclear torpedo at American forces. Similar with Stanislav Petrov in 1983, although it's an open question as to how the leadership would have reacted had he informed them of the supposed attack. In 1995, Russia came within two minutes of deciding to "retaliate" in response to a scientific rocket launched from Norway. A slightly different trajectory or radar reading could easily have made the difference there.

Given the past 71 years, the risk of accidental nuclear war appears to be fairly low. However, we have no real idea if "fairly low" means the risk is 1% per year or 0.000001% per year. Both are consistent with what we've seen, but the former means that nuclear war is extremely likely in the medium term, while the latter means we can probably ignore it.

What are the worldwide rates of interracial marriage? I see in the US (a country where the majority race makes up about 60% of the population) that it's now around 10% for new marriages, and has historically been much much lower. If your statement were true, wouldn't we expect to see much higher rates of interracial marriage than 10% in the US? Wouldn't we expect that the historical rate was also much higher?

What were these higher rates you refer to? Were they as high as would be expected if humans 'enthusiastically' interbred, or even as high as would be expected if humans had no preference one way or the other?

According to that document, in 1890 (I chose that year because the document actually clearly describes the classification criteria for that year, unlike other years it mentions), the "Negro population" was 7.5 million, of which 1.1 million were "Mulatto" and 6.3 million were "Black" (there are some rounding errors here; see document for more exact numbers). The definition used in that census was that "Mulatto" only included people with at least one white grandparent; this would obviously include the ones with a white parent as well. This doesn't directly tell you anything about interbreeding rates per se because there may have been systematic differences in the numbers of children different types of couples had. But it does indicate that even in the 19th century a fair number of children who had at least one black parent also had a white parent. Somewhere between 1/14 and 1/7, if I'm running the numbers right (the former corresponds to a "mulatto" having one "white" grandparent and three "black" ones, while the latter corresponds to having a "white" parent and a "black" parent).

I don't have exact numbers, and no one does that I've seen. Due to social disapproval people tended to keep such activities somewhat hidden.

That said, genetic analysis of African-American populations shows a significantly higher percentage of European-origin genes than can be accounted for by marriage rates, yes?

> Were they as high as would be expected if humans 'enthusiastically' interbred

What rates would you expect? To make this more specific and avoid questions of lack opportunity vs lack of enthusiasm, what rate of slaveowners having children with at least one of their slaves would you expect under the "enthusiastic" hypothesis?

(There's the complicating factor that in that situation at least one of the parties here might or might not have taken measures to avoid pregnancy even if sexual intercourse did occur; it's not clear to me how to account for that.)

Yes, and a much lower percentage of European genes than you'd expect if there were no preference one way or the other for interracial breeding, and a much much lower percentage than you'd expect if humans enthusiastically interbred.

>What rates would you expect? To make this more specific and avoid questions of lack opportunity vs lack of enthusiasm, what rate of slaveowners having children with at least one of their slaves would you expect under the "enthusiastic" hypothesis?

In the early 1800's, blacks were about 20% of the population, and whites were most of the rest. If there were no preference one way or the other, we'd expect 20% of children of white women to be fathered by black men, and 80% of children of black women to be fathered by white men. If the actual rates are lower than that, then some kind of self-segregation is happening.

Pointing out that slavery or other social institutions limited the rate of interbreeding is not an argument in favor of the idea that humans enthusiastically interbreed. If when living in close proximity they tend to set up systems that limit interbreeding, that is evidence that they don't enthusiastically interbreed.

>(There's the complicating factor that in that situation at least one of the parties here might or might not have taken measures to avoid pregnancy even if sexual intercourse did occur; it's not clear to me how to account for that.)

We don't have to account for that because we're discussing rates of interracial breeding, not rates of interracial sex.

Yes, but this ignores the geographic inhomogeneity of both populations. For example, in Boston blacks were a much smaller fraction than 20%.

Obviously if you're white and you live in a village in which everyone else is white too, your chances of having kids with someone who is not white are pretty low. This is why I suggested the more specific metric.

> then some kind of self-segregation is happening.

You're assuming either homogenous population distribution or a lot more population mobility than was happening at the time, I think. That is, you can conclude there is segregation in mating, but the extent to which it's _self_-segregation is a much harder question.

Also, there were non-racial and non-geographic sources of segregation, like class/income. Note the comments in the wikipedia link below about black/Irish couples being a thing because the Irish were very poor.

I'm pretty sure it's possible to account for these effects and discover that there were still racial self-segregation effects, but they will not be nearly as large as a naive 80-20 calculation like yours would suggest. They would, I expect, be larger than the (also existing!) self-segregation effects amongst white people of different ethnicities.

An interesting thought experiment here is what you would expect to happen if you drop two (cis, straight) people of opposite gender but different races on a deserted island for a few years and how this compares to what happens when members of different subspecies are placed in proximity to each other with no other available mating partners. I don't know the answer to the latter, unfortunately.

> Pointing out that slavery or other social institutions limited the rate of interbreeding

I'm not doing that, precisely for the reasons you describe. I'm suggesting that limiting to my specific scenario removes issues of access due to population distribution effects and asks a specific question: given a white male who has the option of having children with black females (yes, the "enthusiasm" is very not symmetric here), what is the chance he will do so? Yes, this ignores the white-female-black-male case (though according to https://en.wikipedia.org/wiki/Mulatto#Antebellum_era claims this was also going on; I'd have to look up numbers on "free people of color in the 1790–1810 censuses in the Upper South" to have an idea of how common it was).

> We don't have to account for that because we're discussing rates of interracial breeding

Well, we're discussing level of enthusiasm. Which as I said above was probably not symmetric, for reasons not necessarily related to race per se. I expect male white masters of female white indentured workers were also more enthusiastic about having kids than the workers were.

The fact that the races end up living in different areas is strong evidence that when put in close proximity, different races don't want to interbreed.

>You're assuming either homogenous population distribution or a lot more population mobility than was happening at the time, I think. That is, you can conclude there is segregation in mating, but the extent to which it's _self_-segregation is a much harder question.

The vast majority of blacks came over as slaves. That means they all started out living in white areas. If they later chose to move away from white areas, for whatever reason, I don't see how anyone can possibly argue that they interbreed enthusiastically. When they find themselves in close proximity, they choose to segregate by race.

>Also, there were non-racial and non-geographic sources of segregation, like class/income. Note the comments in the wikipedia link below about black/Irish couples being a thing because the Irish were very poor.

The reason for segregation is not relevant, as long as it's not a one-off occurrence. If the segregation occurs because the dominant race prevents the subordinate race from succeeding economically, segregation is still occurring.

>what is the chance he will do so?

This doesn't give us any insight whatsoever into the question. We'd have to compare this to how white men behave when they have white women as slaves.

>claims this was also going on

There's no doubt that some interracial breeding was occurring. There's also no doubt that it's far less than would occur if there were no preference one way or the other for interracial breeding, and far far less than would occur if humans enthusiastically interbred, rather than self-segregating when given the opportunity.

>Well, we're discussing level of enthusiasm.

I don't think we're talking about how emotionally happy humans are when doing something, I think we're talking about how likely a certain event is to occur. The overall topic is whether humans can be considered sub-species, and the argument was that they shouldn't be because they interbreed enthusiastically. I'm pointing out that they don't actually end up interbreeding nearly as much as you'd expect if, for some reason, they had no way of distinguishing members of their own race from members of other races.

That's true, but (1) that's not what I was talking about; I was talking about geographic inhomogeneity in original migration patterns and (2) this argument applies to ethnic/language/religious groups in general, not just races. More on this below.

> That means they all started out living in white areas.

Sort of. https://en.wikipedia.org/wiki/List_of_U.S._states_by_histori... shows that in 1850 South Carolina had 668k people of whom 385k were enslaved (hence not choosing where they lived, exactly). I didn't look up the number of free blacks, but I expect it was quite small given the laws about re-enslavement at the time. Anyway, more like the white people were living in a black area there. ;)

But the real point is that for a while there various parts of the country did _not_ have appreciable black populations because slaves had not been brought there while your typical plantation had a much larger black population than white population. Voila, _involuntary_ geographic inhomogeneity.

> The reason for segregation is not relevant

That really depends on the question you're trying to answer.

> We'd have to compare this to how white men behave when they have white women as slaves

Sure. But the worst case for the "enthusiastic" hypothesis is that in this situation they always end up with kids, right? There may be value in comparing to this worst case, even.

> There's also no doubt that it's far less than would occur if there were no preference one way or the other for interracial breeding

Sure. I don't think anyone reasonable is arguing there was no preference on the matter.

But if we're going to talk about sub-species, exact frequencies and cutoffs do matter if the whole thing is to make sense other than as a mood-affiliation labeling exercise ("_these_ two groups are different sub-species, but these two other groups are just less likely than average to intermarry/interbreed"). There is good data showing that breeding across religious and language boundaries is less common (and was even less common in the past) than breeding within those boundaries. And yet very few people nowadays will argue that, say, the French and the Germans are separate sub-species, or were separate sub-species 100 years ago. Yes, I realize that 100 years ago people were in fact likely to make just such an argument. :)

Heck, inter-political-party marriage is a lot less common than within-political-party marriage in the US. And the rate of inter-political-party marriage, in the US, is dropping, while the rate of interracial marriage is rising. According to http://fivethirtyeight.com/features/how-many-republicans-mar... the former is sill more common than the latter but not _that_ much more common. I expect the lines to intersect within the next decade or two if current trends continue...

I guess we could argue that sub-species boundaries are malleable and they can merge or separate over a timescale of a few generations. That would be a valid take on the whole thing, I guess, but then I question the usefulness of the "sub-species" labeling; it seems to not have a useful definition in this situation from my point of view.

OK, but that doesn't take away from the fact that it applies to races.

>Sort of. https://en.wikipedia.org/wiki/List_of_U.S._states_by_histori.... shows that in 1850 South Carolina had 668k people of whom 385k were enslaved (hence not choosing where they lived, exactly). I didn't look up the number of free blacks, but I expect it was quite small given the laws about re-enslavement at the time. Anyway, more like the white people were living in a black area there. ;)

Haha fair enough, but in this case we'd expect interracial breeding rates in certain areas to be extremely high (approaching 50%) but we see nothing even close to that.

>But the real point is that for a while there various parts of the country did _not_ have appreciable black populations because slaves had not been brought there while your typical plantation had a much larger black population than white population. Voila, _involuntary_ geographic inhomogeneity.

If the rates of interbreeding are diminished because one race purposefully holds the other race in small confined geographical areas, that's still an example of interbreeding being limited despite close proximity (i.e. less than a few miles).

>Sure. I don't think anyone reasonable is arguing there was no preference on the matter.

Someone was arguing that there is a preference for interbreeding. That's what this discussion started over -- a claim that humans 'enthusiastically' interbreed.

>And yet very few people nowadays will argue that, say, the French and the Germans are separate sub-species, or were separate sub-species 100 years ago.

You're missing the crucial first criteria for subspecies, which is that they must be "separate groups that are clearly distinct from one another". Frenchmen are not clearly distinct from Germans. White republicans are not clearly distinct from white democrats. White catholics are not clearly distinct from white protestants. White people are clearly distinct from black people.

Really? You think that walking up and trying to talk to one won't make it obvious which is which within about 30 seconds?

If you really prefer, replace French and Germans with Swedes and Italians. Even the visual appearance there is not that far off from the visual appearance difference between "white" and "black" as the terms were defined in the US in the 19th century. In both cases you can find some people that can "pass" as the other group, but the typical members look quite different.

I'm clearly talking about ethnic Frenchmen and ethnic Germans. I would not be able to tell an ethnic German raised in France from an ethnic Frenchman raised in France.

>replace French and Germans with Swedes and Italians.

Northern Italians I think you'd have trouble telling from Swedes. Southern Italians can trace a lot of their ancestry back to non-Europeans and so look different.

Members of the two groups would have had no trouble telling each other apart.

The fact that you think cranial capacity is a "looks different" that would affect people's choice of sexual partners is ... odd. It's not something you can tell from the outside, typically.

Is there actually any science behind that? I'm under the impression that it's not actually possible to identify any ethnic groups based on the stereotypical jew nose.

>The fact that you think cranial capacity is a "looks different" that would affect people's choice of sexual partners is ... odd.

I don't think that. You're asking me if Jews and Poles were different sub-species. Different sub-species must have different patterns of attributes. It doesn't have to be an attribute that people sexually select for, or that can be observed from the outside. I'm asking whether scientists could find such different patterns of attributes. My guess is that the answer is that there wouldn't be anywhere near sufficient differences to warrant considering them a sub-species, but I don't have near enough information to say.

> The variation among individuals is noticeable and follows a pattern, but there are no clear dividing lines among separate groups: they fade imperceptibly into one another. Such clinal variation always indicates substantial gene flow among the apparently separate groups that make up the population(s). Populations that have a steady, substantial gene flow among them are likely to represent a monotypic species, even when a fair degree of genetic variation is obvious.

That sounds like humans to me, so I think we would be considered monotypic. Perhaps before globalization this would not be so.

[1]: https://en.m.wikipedia.org/wiki/Subspecies

Claiming that orange makes red and yellow one and the same is the continuum fallacy. It does not follow that an intermediate population must be evidence of substantial gene flow between populations, rather simply that contact exists. What does substantial mean anyway?

Moreover most human ethnic groups probably do not have "substantial" gene flow between one another, else how did they arise in the first place? With no data to back the claim up I guess less than 5% of people are "racially mixed".

This sort of motivation is not unknown in the social sciences: http://www.rci.rutgers.edu/~jussim/unbearable%20accuracy%20o...