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Unfortunately, not even this holds. Many sexual species can and do hybridize, especially in plants. To answer the original post - as evolutionary divergence is continuum, any demarcations on it are to a degree arbitrary. The justifications for such delimitations have been a topic of considerable discussion, with multiple conceptualizations of what species represent being presented. e.g. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5910646/ The one I would consider the predominant concept among taxonomists is the evolutionary species concept - whereby the ultimate goal of taxonomy is to put name to independently evolving lineages of organisms using multiple lines of objective measurement (morphology, genetic distance, reproductive isolation, ecology, geographic distribution, etc) to validate the lineage. Of course, that leaves little that is generalizable about what makes a species - apart from that it has a evolutionary trajectory distinct from its closest relatives. Clear as mud.

I was under the impression that while WIV had a BSL4 fairly recently, they did previously a lot of agricultural and environmental microbiological research, which would be BSL1/2. While I do not know their current organization, I would be surprised if they gave up all those laboratories. Edit: I got curious and checked their website, in addition to the BSL4 facility (from which leaks are highly unlikely) there are two BSL3 facilities (more likely, breaches happened in the UK) and 17 BSL2 facilities. Animal samples would likely be handled in those. So at least from the available information I do not think that we can conclude that the reports specifically refer to leaks from the BSL4 facility. Though admittedly, I have not been following the news very closely, as I do not think that there are a lot insights to be gained from this.

Eh, the Omicron variant has a very high transmission rate, which is why its presence is ubiquitious now.

Interesting. The BBC article doesn't explain how it works but I've found this paper with an abstract and a diagram that help explain this: https://www.sciencedirect.com/science/article/abs/pii/S0306261920311776 Here is the diagram: It seems from this that these microbes generate CO2 and H+ ions by decomposing organic matter below the surface of the soil and in the process release free electrons (!). The electrons are captured by the anode of the circuit. The cathode lies on the soil surface, which is exposed to oxygen in the air. There, H+ ions are combined with oxygen plus electrons from the cathode to produce water. So the net effect is oxidation (electron removal) of the organic matter, producing CO2 underground and water on the surface. The slight mystery is that this paper is from 2 years ago, so it seems unclear why the BBC has decided to report it as news only now.

Pretentious. (to me) 🙃 I rate Chuck Berry as America's greatest poet. Dylan could never have written Johnny B Goode, or Nadine.

I mentioned that, with modern human/neanderthals as an example. But what I said does hold, in that if they don't regularly interbreed, and produce viable offspring, they are considered a separate species. The term viable offspring is the fuzzy, debateable part. It really means, produce a viable population of offspring. If two species can do that, then it's very debateabe whether they are separate species or not. If you take the example of the carrion crow, and the hooded crow, then as a general rule, there will be an area where it's all hoodies, and an area where it's all carrion crows, with a narrow border area between them. Around the border area, you will find hybrids, but away from the border, you get one, or the other. So you don't get a successful self-sustaining population of hybrids, so they are still considered separate species. The only substantial difference between them is the colour pattern, but that's enough so that a hoodie that migrates into the territory of carrion crows will not attract a mate, and vice versa, because they look out of place. But in the narrow border area, the birds get confused, because they are regularly encountering both colours, and they don't know which they are, so they don't know which to mate with. So you do get some hybridization, but not enough to form a self-sustaining population, so they still get classed as separate species. In the plant world you get a similar situation, but for different reasons. The Linden tree for example, in my area, has two common species, the broad leaf and the small leaf lime. They do readily hybridize, but even so, they tend to separate on a population level into areas where nearly all trees are one, or the other, and the hybrids don't form a self-sustaining population. I don't think it's known why that should be, probably something to do with the soil or small climate differences, enough to favour one over the other. So even though they readily hybridize, they still maintain separate populations. But like the crows, you do get areas where you will find both, and hybrids.

reported as well. Are you reporting yourself? No wonder you can't handle a sign inversion.

Seemed like it was time to listen to one of my country's greatest poets again - Bob Dylan: Will this song ever not be timely?

Yes. a study in 1990 found that genetics account for 50 percent of the religiosity among the population — in other words, both identical twins raised apart were more likely to be religious or to be not religious, compared with unrelated individuals. https://www.livescience.com/47288-twin-study-importance-of-genetics.html Search on studies on twins reared apart or studies on separated twins

I am a relativity amateur, but this one is even clear to me: you should of course use the same dimension for velocity for v and c: both in m/s, or both in km/h. But if you set c = 1, then you should express v as a fraction of c. This is such a beginner's error, that I don't have to take the rest of your exposés seriously.

The numbers are not normalized by cost of living. Rice, for example, costs ~4x as much in the United States as it does in Vietnam. So an expenditure that is 4x higher does not mean they are eating 4x more. https://www.numbeo.com/cost-of-living/country_price_rankings?itemId=115

It's a good start for General Philosophy though.

I don't know what you mean by "it's a physical parameter, and not a mathematical one." A physical parameter, in the usual sense of the term, most definitely it is not. A physical parameter is any quantity that we can vary either freely, or subject to some specified conditions. Eg, the magnetisation of a medium of given magnetic susceptibility, etc. In the context of relativistic physics, c is a universal constant, not a parameter. Theoretically, it is derived from principles of electromagnetismf. Experimentally, it is measured. If you mean otherwise, you should say so. Because I've been studying these things in excruciating detail for many years, I can tell you you're using the poor-man's version of boosts. The grown-up version of it is, \[ \boldsymbol{x}_{\Vert}'=\frac{\boldsymbol{x}_{\Vert}-\boldsymbol{v}t}{\sqrt{1-v^{2}/c^{2}}} \] \[ ct'=\frac{ct-\boldsymbol{v}\cdot\boldsymbol{x}/c}{\sqrt{1-\left\Vert \boldsymbol{v}\right\Vert ^{2}/c^{2}}} \] \[ \boldsymbol{x}_{\bot}'=\boldsymbol{x}_{\bot} \] Where you have to decompose position 3-vector \( \boldsymbol{x} \) as, \[ \boldsymbol{x}=\boldsymbol{x}_{\Vert}+\boldsymbol{x}_{\bot} \] \[ \boldsymbol{x}_{\Vert}=\frac{\boldsymbol{x}\cdot\boldsymbol{v}}{\boldsymbol{v}\cdot\boldsymbol{v}}\boldsymbol{v} \] \[ \boldsymbol{x}_{\bot}=\boldsymbol{x}-\boldsymbol{x}_{\Vert} \] So the expression in the numerator is actually not a positive 3-scalar, but a 3-vector projection in some inertial frame. You don't understand anything, and what's worse, you don't ask. So Markus's noble attempt to help you, my attempt to close down possible loopholes, and other members' attempts to walk you through the logic of Lorentz transformations, is --most unfortunately-- to no avail. Pitty. Good day.

You have provided incoherent nonsense. You're boring us, Mr. Bahari. Please post something funnier. 😄 Length contraction: [math]L' = {x'}_2 − {x'}_1 = \gamma(x_2 − vt)−\gamma(x_1 − vt)=\gamma(x_2 − x_1)=\gamma L[/math] Time dilation: [math]\displaystyle{\Delta t' = {t'}_2 − {t'}_1 = \gamma\left({t_2} −\frac{vx}{c^2}\right)−\gamma\left({t_1}−\frac{vx}{c^2}\right)=\gamma\left(x_2 − x_1\right)=\gamma\Delta t}[/math] No dependence on the sign of v. 😉

c can have any value you want just by choosing the length and time units accordingly, as @Eise told you. Stop blaming your misunderstanding on others. I also told you.

span widget When the S is stationary and S’ is moving, what you are saying is that the term x'=(x-vt) in the Lorentz formula is in the Galilean-Newtonian mechanics and does not relate to SR. OK, this is true. In Newtonian mechanics, when we use the negative quantities for v, you will use x'=(x+vt), instead. Example: x= 10 m t= 2 s v (S’ velocity) = 3 m/s x'=(x-vt)= 10-(3)(2)=4 m For v= -3 m/s --> x'=(x+vt)=10+(3)(2)=16 m However, in Lorentz transformations, we are not going to use x'=γ (x+vt) and t'=γ(t+vx/c2) in the case that S’ is moving with the speed v to the left (for instance v = -108 m/s) and in any papers, texts, books, etc about the SR, nobody use such terms for Lorentz equations, in the case that S’ is moving to the left. Not Lorentz, nor Einstein, nor any other people. All the times, everybody use the main formulas, whether the S’ frame is moving to the right or to the left. Have you asked of yourself, why? That is because the Lorentz formulations have been invented to consider the light speed to be constant to c when it is propagated spherically for both S and S’ frame: metrics invariance for both S and S’. Before I make an example, I will derive the Lorentz equations when a light signal is propagated spherically : 𝑥 2 + 𝑦 2 + 𝑧 2 − 𝑐 2 𝑡2 = 𝑥 ′2 + 𝑦 ′2 + 𝑧 ′2 − 𝑐 2 𝑡 ′2 = 0 --> x=ct , x'=ct' x'=γ (x-vt) --> ct'=γ (ct-vt) x=γ (x'+vt' ) --> ct=γ (ct'+vt') 𝑦 = 𝑦’ 𝑧 = 𝑧’ t=γt' (1+v/c) t'=γt (1-v/c) t'=γ^2 t' (1-v/c)(1+v/c) γ=1/√(1-v2/c2 ) For instance, suppose the S frame is stationary and the S’ frame is moving to the left with a constant velocity v = 108 m/s. When the center of coordinates (zero point) of these frames is coincided with together, a light signal is propagated from this point spherically (suppose in the figure 1, S' is moving to the left instead of moving to the right). At this moment, the clocks of both S and S’ observers which have already adjusted together, start to work. We want to calculate the light coordinate in both S and S’ frames after 2 ms. In the S frame: t=2 ms x=ct=3×108×2×10-3=6×105 m =600 km In the S’ frame: with employing the Lorentz transformations, we obtain: x'=γ (x-vt)=1.06 (600-108×2×10-3)=424 km t'=γ(t-vx/c2 )=1.41 s Graphically, you can find that the quantities we have achieved with these formulas for the light signal coordinate for S’ is not true quantities for positive axes of x’. However, since the light is propagated spherically, for negative axes of x’, it becomes true. I mean when the x=ct=-600 km --> x'=-424 km Therefore, we can neglect the sign of x and v in Lorentz transformations and always use the main formulas, whether S’ is moving to the right or left. But if you persist to use x'=γ (x+vt), when the S’ is going to the left, it is OK. However, when you reverse the formula to x=γ (x'-vt'), you must not to apply v reversal, as Dr. Rindler says, to make them symmetrical. If so, you would find γ=1/(1+v/c) which is less than 1 and so, your length would be elongated and time becomes faster. Now, you can go and find something funnier. First, the light speed is a universal constant c = 3*108 m/s. It is not equals to 1. So, when you use the c in the equations, if you want to simplify your mathematical equations, you can use c=1 instead. However, when you want it as a physical constant paprameter, you are not allowed to use c=1. For instance, in the Lorentz equations β= v/c is a number between 0 to 1. But if you put c=1, β= v/c is a number equals to v which could be much larger than 1. Therefore, it is wrong to use c=1 in the Lorentz formulas. Second, as a physicist, you are supposed to simplify the equations not to make them more complicated by copy and paste other derivations of them for electrons inside the magnetic fields and we have from the Internet. Yes, absolutely there are other derivations of the Lorentz transformations in 4 dimensions. But, I am using the simple and completely applicable original Lorentz equations only for x direction, intentionally to explain why these equations are not symmetrical: You have the equation x'=γ (x-vt), when you reverse it, you will find x=γ (x'+vt) , these two equations are not the same, so they are not symmetrical. You have the equation t'=γ(t-vx/c2 ), when you reverse it you will find t=γ(t'+(vx')/c2), these two equations are not the same, so they are not symmetrical. We are not allowed to change the v sign, when we reverse the equation. Because we are performing just an arithmetic job, not changing the observer. Third, after a PhD in nuclear physics and Ms. And Bs. In engineering and writing many outstanding papers that published in the ISI journals and teaching several years in the university and 10 years of hard studying about the SR (at least 200 papers and 20 books) and deep thinking and learning, yes I can not understand the bullshits you add to my comments like "Λ(−v)Λ(v)A=IA means the symmetry of two equations" or γ' or other wrong statements of yours. But, what I understand is that I am talking to some young boys who ever in BS or lesser period and try to discuss with others without even study and learn their papers. This is crazy. I taught I am discussing with some literate people not some dogmatic people who try to speak fast and loudly without even studying and hearing the words of the person in front of them. If I knew, I did not discuss with you never. · Please search in the internet and find the symmetry means. If you can prove that Λ(−v)Λ(v)A=IA means the symmetry of two equations, I will accept your words, or else, please shut your mouth and first, study, then talk. · My attempt is not anti-relativity completely. I have accepted the invariant of the Lorentz equations, but, I do not agree with that they are symmetrical. · All the experimental tests agree with the above-mentioned claims. For instance, the atomic clock inside the moving high-speed airplane is dilated with the gamma factor, but the stationary atomic clock on the earth is not dilated. The researchers test the Lorentz formulas for the moving frames and get results for the Lorenz invariance of the inertial frames. However, they have ignored to test the Lorentz formulas from the view of the moving observer who thinks he is at rest according to what the SR says. Therefore, what they actually achieved is the Lorentz invariance not the symmetry of the inertial frames. · My paper after 5 month from its publication by a refereed journal was taken into account much more than I expected. In your forum, you mentors do not allow the others to speak. You just want to speak what you have learnt already in your books. But the real researchers are open- minded persons who do not think that all the matters in the books are true. They are finding the false theories. Just search how many famous scientists are completely or partially against relativity (you can find it in my paper). · About what you said I do not want to understand the negative value in the equation, read my answers to other. · But, whenever, some dogmatic people are dominant on the world of science, they could not be successful to talk and make their theories worldwide spreading. I do not want to say the journals should publish bullshits. But, I want to say the new theories if they are elaborated scientifically, must be published. Recently a published research showed that the velocity of the progress of science decreased rapidly in recent years. The reason is exactly those dogmatic people in the world of science today. Unfortunately, the people like you, when they have not enough logic in their hands (mathematical or physical logic), try to humiliate the person against them. That is the method of not literate and not civilized persons and I am so familiar with such people. I again recommend you to study more and then come and discuss with honorable people. Just search my name then open your mouth and say bullshits.

-1. You would be well advised to stop insulting people and clean up your own house. Neither one of us is "dominant in the world of science." As to you, you are nowhere near the world of science. Reported.

I did not put c=1. others who were discussing with me did it, and I replied to them.

shut your mouth and stop humiliation. I think you even not literate in the kindergarten level. reported as well. Unfortunately, when I discussed and rejects their math and physics by strong math/physical logic and made them empty of any objection, they had to try humiliate and insult me. This behavior belongs to people who are not scientific, not literate and civilized. I have reported them. Please follow up this matter. Regards. False statement. Go and read what I wrote to you again.