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  1. 7 points
    So looking at the image below, it appears that Galagidae have recognizable soles, but Cynocephalidae do not : and when we look at a primate phylogeny, we see the split between these two groups is around 65 million years ago: So soles originated about 65 million years ago, give or take. You meant soles as in soles of the feet, right?
  2. 5 points
    Brevity and sarcasm. No wonder no-one knows WTF you're talking about half the time.
  3. 4 points
    That's not a fact - e.g. polyploidy. If you aren't equally weighting all mutations, none of the math in the entire post makes any sense. This probabilistic numerology argument is not new and founded in foundational misunderstandings of genetics and evolution: DNA encodes amino acids in triplicates of base pairs called codons. There are 64 possible codons, encoding 20 amino acids, and stop. The translation of codons into amino acids is highly redundant, with numerous codons denoting each amino acid. 61 encode amino acids, and three encode stop. There are no untranslatable codons. This has a number of implications:  1) All possible DNA sequences can be translated into proteins. There is no such thing as a "gibberish" DNA code. 2) Because of the redundancy, multiple changes can occur without affecting the translation of the sequence. 3) Arguments from low probability are not apt. Given all possible arrangements of nucleotides can encode proteins, there are no null sequences. Consider it more like a dice throw. Rolling one hundred sixes in a row has a probability of (1/6)100 or 1.5 x 10-78. Except ALL combinations of 100 throws have this probability and if you perform the experiment, an outcome is inevitable. Claiming that the low probability makes the outcome impossible ex post facto is not sensible. If you're open to it, a major component missing from the argument posed is explained by the concept of fitness landscapes, which allows one to model the adaptation of a population given different likelihoods of each possible mutation proliferating in a population through time. The entire landscape would be all of your "unrealized genomes" but because of the weighting of selection on certain regions of the landscape, some mutations are more likely to fix than others. Step size on the landscape can change drastically if large scale mutation like translocation, duplication or deletion occurs (i.e. not all changes are incremental). See https://www.sciencedirect.com/science/article/pii/S0022519396900491 https://www.mitpressjournals.org/doi/abs/10.1162/106365602317301754 https://onlinelibrary.wiley.com/doi/abs/10.1002/(SICI)1097-0134(199712)29:4<461::AID-PROT6>3.0.CO;2-B etc.
  4. 3 points
    I'd say early to mid-twentieth century. But it wasn't God, at least not directly. It was Ray Charles.
  5. 3 points
    Not at all. Inflationary theory is part of the BB scenario and was added to explain a couple of anomalies, namely the Flatness and Horizon problem. The main proposal of the BB, is that the universe/spacetime evolved from a hot dense state. We have ample evidence that this is so. https://en.wikipedia.org/wiki/Big_Bang Timeline of the metric expansion of space, where space (including hypothetical non-observable portions of the universe) is represented at each time by the circular sections. On the left, the dramatic expansion occurs in the inflationary epoch; and at the center, the expansion accelerates (artist's concept; not to scale).
  6. 3 points
    Apologies, I misinterpreted and thought you meant a few weeks in the literal sense, and yes, I knew that - I was making an analogy to a well established scientific theory and an inappropriate alternative hypothesis rather than trying to directly comment on your own example. The point was that evolutionary theory does have plenty of alternative mechanisms and hypotheses - it's just that ID insists that none of them are adequate and there HAS to be a supernatural explanation. It's not really the case that it is one explanation or the other.
  7. 3 points
    I hate to spoil the fun, but it really is "just deserts", not "just desserts"! The "deserts" is a noun related to "deserves". To quote from Garner's Modern American Usage: Obviously this is the most important thing I have to do in the office on a Monday morning.
  8. 3 points
    You asked if karyotypes were sexes. Karyotype is simply a term for the arrangement of chromosomes within a eukaryotic cell. Variation in the karyotype of sex chromosomes results in sexes in sexually reproducing species. So no, Karyotype is not synonymous with sex. The author is assuming that sex is defined by karyotype - which is a little problematic. As alpha reductase syndrome is a good example of, a individual with this condition is karyotypically male, has undescended testes, but has female external genitalia. So does the karyotype, the gametes, or the phenotype define the sex of an individual? Personally I wouldn't define monsomal X and a "sex" per se, implying that Homo sapiens is a multi-sex species, but I would say that an individual with monosomal X (i.e. Turner's syndrome) falls outside the standard definitions of male and female. The article states that the individual will be chromosomally XY, have female external genitalia, and are usually raised as girls. I don't really care if the article uses the specific word "intersex". People with the condition have characteristics of both sexes - and are therefore intersex. Ergo, listed as an intersex condition by the Intersex Society of North America Honestly, I don't care if you support him one way or the other - I'm simply stating that biology doesn't - sex isn't binary or universally fixed at birth. Turner's syndrome (monosomal X) results in phenotypically female individuals - there's no Y chromosome to provide male genes. However, having a single copy of all of one's X linked genes is going to significantly alter the expression patterns of all of the genes on that chromosome, resulting in physiological abnormality. Also, the chromosomal imbalance during meiosis will result in reduced fertility.
  9. 3 points
    Glass is a bit different as to why it is quickly cooled to harden. When glass is cooled rapidly the outside hardens first and then the inside of the glass cools and contracts. This puts the surface of the glass into compression. Glass breaks under tension, not compression, so the glass is much tougher. Since there is so much stress in the tempered glass, when it does break it goes into a gazzilion (technical term) pieces. Gorilla glass (think cell phones) is hard because large ions are exchanged for smaller ions in the glass and it again puts the glass surface in compression. If you are familiar with Corelle brand dishes they are so strong because they are made with a glass laminate process and the inner laminate has a higher CTE so when the glass cools after the lamination step the inner glass shrinks more and places the surface in compression. Tempered glass is not permanently hard, if the glass is taken up to the glass transition temperature the stresses will be relieved and the hardness will drop back to 'normal'. I work for a glass/ceramic company and my wife is a glass technologist - could you tell?
  10. 3 points
    Yes, he is, but QuantumT is using "you" to refer to all mods, and specifically referring to me in terms of shutting threads down. If the speculative thread dealt with physics, I'm the mod most likely to have interacted with you (over the years) Is it too fast? Well, that depends. We have received comments where people have complained about threads being left open too long, and begging us to close them. The people whose thread was shuttered rarely agree that they should have been locked. Bottom line is that there is no moderation strategy that will please everyone. The mods use their best judgement, built upon doing this for a number of years, and seeing a lot of people come and go. You in particular? In your first thread I tried to nudge you into compliance with our rules. That you needed to be more forthcoming with information. The thread was shut down after you announced "I will not participate in this open forum anymore" But you weren't true to your word. You came back, and to be honest, you lose a certain amount of goodwill from the mods when you pull a stunt like that. Once again, you were not forthcoming with information needed to support your position. That thread was closed, with a note that said if you did present supporting information, you could re-introduce the topic. I don't see where you took us up on the offer. The last one shut down was where you admitted you didn't understand the physics, and yet had a conjecture. I explained that this was not living up to our expectations, and at this point you had twice been given feedback on the matter of being able to support your ideas. Thus I had zero confidence that simply giving some feedback and letting the thread continue would improve matters. That was your third strike. The fact that you are placing the blame elsewhere tells me you haven't absorbed this feedback at all. So the question that I have is how many chances do you expect, when you show no improvement in your behavior?
  11. 3 points
    Alrighty, I have a reasonable level of experience as a phylogeneticst and systematist. In contemporary systematics, the word race is generally used to describe different karyotypes within the same species. As humans are generally all 2n=46, the use of the word race to describe phenotypically or genetically distinct groups of humans is somewhat antiquated. Subspecies is a bit of a squishy topic, insofar as it is more a categorization of convenience than one with objectively defined characteristics. Generally, it defines a group with some diagnostic molecular or phenotypic characters, or groups with allopatric distributions, but some degree of admixture between them. One could pose an argument that different populations of humans are "subspecies", but there are a number of reasons why not: 1) Humans are a very, very recent group with very limited genetic diversity. 2) Genetic differences between human populations are generally clinal (with some exceptions of course). 3) Phenotypic traits are generally not fixed between groups of humans, and exist in a plethora of intermediate states. 4) The argument is all too often underlain by some sort of racist pseudoscientific motivation. While there is certainly valid population structure within Homo sapiens, and one could make an argument to taxonomically split the species into subspecies, I would imagine that such a designation would be of limited practical utility, fraught with ethical dilemmas and unlikely to be widely adopted. Edit to add: People publishing novel taxonomic arrangements that no one else agrees with happens all the time. If it's bad enough, scientists in the field will simply ignore the erroneous classification, then get super annoyed that when you do revise the group properly, the International Commission of Zoological Nomenclature code dictates you have to use the existing names the crackpot registered.
  12. 3 points
    Matter and galaxies do not expand, their binding energy is far stronger than the energy supplied by the cosmological constant. So no this is inaccurate to describe why the universe expands. lets try a little lesson. Pick any number of arbitrary points, as expansion occurs those points gain separation distance. However and this is the critical part, the angles between any two or more points do not change. This describes a homogeneous and isotropic expansion. So there is no flow of matter from some centre to the outer regions. Expansion occurs in all directions equally. If you think about this then consider the directional direction component of how forces work, then one also has to realize that no force style effect can be causing expansion. Take an object such as a star, or galaxy. Apply equal amounts of force on every side and angle from other objects gravity etc. That star or galaxy will not move as the net sum of forces at any given angle is zero. This is because the mass density distribution on all sides of the star or galaxy is equal so any force they may exert is also equal on all angles. In regions where there is zero to minimal binding energy expansion occurs as the extremely low energy density of the cosmological constant term roughly [latex] 7.0*10^{-10} joules/m^3 [/latex] has no binding forces to contend with, however neither does it have a directional component. It is only in regions where there is minimal matter/mass that expansion occurs (without any inherent direction). Now keep the above in mind for any speculation you may have. make sure your speculation can match the above criteria and furthermore match the criteria of no net inflow or outflow of mass/energy leaving or entering the cosmological event horizon. (limit of our Observable universe) simply we cannot get signals beyond this point as it takes time for signals to reach us. Both due to the speed of light as well as expansion rates. These criteria will greatly limit the options that one can speculate on that will fit the observational data. A great deal of professional models were discounted simply due to the extreme uniformity and homogeneous and isotropic distribution of matter. The second criteria can be tested by temperature measurements, so models such as Universe in a black hole/white hole has great difficulty meeting the first two criteria. With the uniformity and non directional component of expansion, the process causing expansion must occur everywhere equally. It can be overpowered in localized regions of matter and still occur (that region will simply not expand as a result). This is the conditions you must match to have validity. The process cannot be from localized sources such as galaxies etc as it takes time for signals to reach other locations limited by the constant c. For this reason must occur at al locations in some process. (simply overpowered by other binding energies in those localized mass densities). There is nothing wrong with speculations, however its a real time saver to know the criteria that one needs to meet and match in observational data.
  13. 3 points
    Originally, there are two major divisions of science - Natural sciences and Social sciences; Natural sciences are disciplines designed to predict and explain events that occur in our natural environment (Physics, Biology, Chemistry...), while Social sciences are usually fields of academic scholarship which explore aspects of human society (law, history, sociology...). From this, it is clear enough to state that natural sciences study the psychical world, and social sciences study human behavior. This being said, we can easily decide in which category does Linguistics fall; Linguistics is known as the scientific study of language and its form, meaning and structure, including the study of grammar, syntax and phonetics. However, Linguistics is a rather vast field of study and it can be divided in specific branches, such as psycholinguistics, sociolinguistics, computational linguistics, etc. According to this official and standard definition, Linguistics seems to fall under the category of Social sciences - since it studies a certain aspect of human behavior. However, linguistics tends to have different aspects of which some of those aspects belong to natural sciences, while others belong to social sciences. For instance, the aspects of linguistics that are related to natural sciences are neurolinguistics or biolinguistics. I think that this mix does not make linguistics and entirely social science, nor an entirely natural science, making it an interdisciplinary subject. But the fact that linguistics not being an entirely social science is not the problem here. The problem is the attitude that people have towards the two main divisions of science; Namely, the majority of people don't really value social sciences as much as natural sciences. And since most people put linguistics under the category of social sciences, they tend to automatically doubts its scientific credibility. But, i don't completely blame them, as they might have a good reason for their opinion. Another important argument as to why some sciences or disciplines of study may not be considered as "real sciences", and that has nothing to do with the fact that one particular science is considered as social or natural; A scientific study must have a valid approach and methodology, based on strong evidence, and not some claims or theories that cannot be subjected to an observational state. And only when these standards are met and achieved, the field of study that is in question can be considered as a real science that has some sort of validity in the overall scientific community.
  14. 2 points
    yesterday was my birthday so I took some time to think. think about how much I have learned(mainly from just looking at posts). and how am better than when I started. and part of that was because of you guys(part was just growing up). there is more but I can't find a good way to say it. p.s sorry for being kind of a shiteposter.
  15. 2 points
    First thing? PUT. THE SHOVEL. DOWN! Claiming you have NO hobbies is ridiculous. You're purposely axing a perfectly good suggestion so you can remain alone. STOP IT. You can't tell me you don't play online games, or watch movies, or follow a TV series, or enjoy some activity that you could do with others for some socialization. Claiming you can't hold a conversation is another generalized negative image you're wearing purposely. You may not be good at it because you don't practice enough, but that's a long way from not being able to do it at all. STOP reaching for the dark paint when drawing a mental image of yourself! You've had some friends (not many, but some), which means your mother can't be your only contact with other people, yet you perceive it that way. I'll tell you something about friends, quantity isn't the key. And the only way to improve the quality is to put yourself out there and be a good friend. If you only have three tight friends by the time you're forty, you can consider yourself blessed. You've been practicing piling up all the negative aspects of your life as a weight that keeps you from doing better. You won't be able to throw all that off at once, so I recommend you start identifying what you want to improve, and make a list and tick the boxes. It's actually not as difficult as you think, because there are plenty of other people JUST LIKE YOU, swimming in a pool of muck you filled yourself. Once you put the shovel down, there's nowhere to go but up. Oh yeah, and this.
  16. 2 points
    You guys are 'quitters'. Isn't there always something else you want to do ?
  17. 2 points
    1. Go back and read the posts you made that received multiple neg reps. 2. Don't be that person.
  18. 2 points
    Ryan, welcome to ScienceForums. Since you have come forward like this I am going to say +1 for encouragement, but you need to be more focused here, like swansont says. In relation to your topic, here are a few hints. Although your topic is in Chemistry, you will need to equip yourself more widely with basic Science, particularly Physics. You will need to know the difference between force and energy, and the different types of energy, particularly potential energy. You also need to have an idea what a particle is. You will also need to know the meanings of the terms atoms, molecules, ions, elements, compounds, pure substances and mixtures. Chemistry is very theoretical. It tends to concentrate on substances the ordinary person does not come into daily contact with and cannot readily obtain, eg nitrogen and oxygen. Seeing that your work in hardware, you may find the more down to earth approach used in Materials Science or Engineering Science attractive. Here the emphasis would be more likely on air in my example. So hardware means things like glue and timber and concrete and rope and so on. Chemists will discuss the forces between individual oxygen atoms - very theoretical. materials Scientist will be more interested in why and how the fibres in a rope hang together to form a length of rope, even though no individual fibre is anywhere near as long as the rope. If any of this gives you inspiration for more questions, I will have achieved my objective.
  19. 2 points
    What is a shadow made of? Shadows certainly 'exist' - whatever that means. A shadow is a prime example of zero something. I think the english language offers a good construction. it = a thing is a noun. Nouns can be 'concrete nouns' like an apple or water or well, concrete. Or nouns can be abstract nouns like anger, a shadow, weight and so on.
  20. 2 points
    “I don’t know anything about how electric cars work but I’m sure we can make a better one based on cheese”
  21. 2 points
    ! Moderator Note When you have a model, then you will have fulfilled the requirement of the speculations forum. You can contact a mod to re-open this thread. But until you have some substance to discuss, and not just hand-waving conjecture, this is closed.
  22. 2 points
    I agree. Your statement made me look at the beginning of the thread again. We didn't get all rules initially, a followup said: So there is no complete English translation given yet? Speculation: What happens if the correction only applies to Jack? So that the following initial statement Actually was supposed to be something like: "Jack only know the range of the digits; meaning he knows that a>=b>=c>=d and he knows a - d (a minus d). John only knows a+b+c+d. James knows a*b*c*d." In other words, is it possible that John and James do not know that a>=b>=c>=d? I haven't yet checked what difference this would make when trying to solve the problem. A maybe even more speculative question: But then they all act in another order: Jack says... James says... John says... Is that change of order the names intentional or was the names mixed up in translation? I haven't yet checked what difference this would make. Can we see the original question? (Even if it's in Turkish it might help at this point)
  23. 2 points
    *sigh* Again, it's not the faulty details themselves that get a thread locked, it's the unreasonable adherence to them in the face of contrary evidence. EVERYONE involved in the threads is trying to teach, but only some are willing to learn. It's a shame that all this comes off as "trigger-happy moderation" instead of the attempt to enhance science discussion it's meant to be. Breaks the heart.
  24. 2 points
    He was referring to what she did. She didn't simply make an opinion. She acted upon that opinion and supported a declared enemy of the United Kingdom. That is treason. Except this is a red herring. Because this is not the case. The evidence is not secret, her parent's citizenship is not being revoked, and it's not suspected actions. It's real actions.
  25. 2 points
    Today, couple hours ago, two young girls (20-25 y) visited me. They were from Jehovah's Witnesses. They gave me some bible ad. I took it. Took couple empty piece of papers and pen. And we sit on the floors. And asked them whether they "believe Universe was created by God?", obviously answered "Of course!". So, I asked "then why do not learn about Universe?", And started from pair production of electron-positron from high energy photon, wrote it on paper, wrote what is mass-energy of electron/positron, first I wrote 9.11*10^-31 kg, then I explained it's just round up, and exact value is 510998.928 eV/c^2 then I explained them what is proper speed of light (they didn't even knew 300,000 km/s), I explained them it's 299792458 m/s, then I started explaining conservation of charge in pair-production (e=1.602176565*10^-19 C). And how light turns to matter and anti-matter. And how to change from eV/MeV/GeV to Joules, and back. And from Joules to kg, and back. Then continued to annihilation of electron-positron, then to pair-production of proton-antiproton. Then to fusion of protons. Now girl surprised me,. She told me than Deuterium with charge +1e won't match with 2 proton also with charge +1e (I told her first that Deuterium is proton and neutron bound together). So she was actually learning/listening for real. I obviously congratulated her for it, and explained that from fusion of 2 protons, there is produced also positron and neutrino and 0.42 MeV energy. Then to how to create free neutrons.. Then to neutron capture, and radioactive decay... I asked them to gave their smartphone, and went to YouTube to show Cloud Chamber videos of radioactive isotopes and explained the basic cosmic rays-atmosphere reactions, producing secondary rays, explained pion meson production, and muons, and showing them on videos how they look like/behave.. That was probably the longest talk with girl I had in the last 10 years I will skip further details.. At the end, they knew how nuclear weapon and nuclear reactors (Uranium-235) do work.. She said something like "you made me feel like really stupid...", "That was not my intention... Did you learn how Universe is working today?" "Yes..."