Human Definition and 880 Threads

Dear PF Forum, It's been a while that I've been wondering. Where did people from particular island in Indonesia come from? Here is the map As I understand it, homo sapiens came out of Africa 70 thousands years ago, and they went to Australia. Is that why that our brothers (and sisters) from...

Hi everyone, In Carl Sagan's Cosmos there's a short animation video illustrating the shape of all human ancestors, starting from single cell organisms, morphing towards the modern humans. I've searched for a complete list of known human ancestors like that one, but I couldn't find anything like...

Homework Statement The number density of 1H nuclei in the body is roughly 600 times greater than that of 13C nuclei. By what factor is the magnetisation M0 of 1H greater than 13C in the same external magnetic field? Homework Equations 3. The Attempt at a Solution [/B] Surely it can't be as...

On the heels of 4 major universities offering racially segregated living areas, at the request of some students, some people decided that didn't go far enough. http://reason.com/blog/2016/10/26/video-uc-berkeley-protesters-built-a-hum']This[/PLAIN] week at UC Berkley protesters decided to...

I will be giving O levels in two sitting for may'17 and jan'18 . I aim to be a heart surgeon. I plan on taking Biology but I am confused if I should take Human biology or not. If I take , I will only be left with 6months of private coaching , I am also scared if I'll be able to bring good marks...

Hello everybody, I encountered this weird theory that I don't really believe to be valid. But it sounds pretty plausible, so I'm going to let you guys tell me whether it is correct or not. Anyway, the link is here: http://www.onelife.com/evolve/degen.html (warning: possible crackpot link)...

I wondered what can be the plausibility level of enhancing human abilities not through implants, but biological modifications? My story involves Mars where the church dislike more advanced AIs, and they seek to upgrade humans. While i speculate growing up in low gravity already changes humans...

Is it true that glands made of muscles and these are the muscles which squeezes out secretion from the glands?

Mirror/camera/TV etc. don't have a complex visual cortex system/perception like our eyes. Human eyes use rod,cone,neuron and above all perception of brain to make image. How come these devices create the same clear images/scenes at their surfaces by themselves without having the advance...

I am writing a blog post about dairy and it suddenly occurred to me to wonder at the value of human breastmilk. That is, if cow's milk is so good for us, yet is from a different species, how would we get on if we drank human milk? A search of the web turned up nothing much at all. A slew of...

I have read a great deal of psychology and I have a very strong feel that the explanation of human soul must lie in the neurology and study of brain signals especially in strong emotional states like listening to strong lyrical rap music or being in love. I want to discuss it here so we can...

I would like to get a handle on human Wattage under various conditions. it would be great to compare theory calculations of say running up stairs with how much ACTUAL wattage it takes...just for physics fun. the only common bench top measurement device I can think of is those wrist-watch type...

A curious question that's come to my mind, as I'm doing a little research for game development, aiming for realism here. Assume you have a human corpse, not doused in any special kind of fuel, but wearing cotton/polyester clothing. And you set it alight, to slowly burn over time. I've heard of...

well if seen from top approach, "dejavu" is just a myth, but if it is observed practically, it happens with me everyday. I think that I am always respecting my actions. I think that there is 30 hours in my day. I think that I am a freak but if it happens a dozen of times, it is no coincidence...

Homework Statement According to the "internet", the efficiency of humans to climb stairs is about 25%. How much energy does a person weighing 80kg use to climb from the 4 flights (12.95m total) floor of the von Haast building?Homework Equations change in potential energy of a system is =...

Ok so what I want to create is a simulation of how the acceleration of a person falling would change according to the person's mass and height. This would then be explored in Matlab. Therefore, first, I am trying to find out the equations that would relate acceleration motion with mass and...

I am interested in hearing more on this, Pro's Con's etc. Any thoughts or info would be greatly appreciated. http://www.nytimes.com/2016/05/14/science/synthetic-human-genome.html?_r=0

Hi All Im hoping I am in the right area to ask this?!? Im looking for someones help. Is there a standard methodology or known equation for generating a random alpha numeric serial or incremental, which does not allow two characters to be used in sequence to each other which are near each other...

Homework Statement I am trying to prove a human head hitting the ground after falling backwards down a hill suffers a significantly greater impact than one hitting the ground on a flat surface. The person is 95KG, 180cm tall, and the impact point of the head was 60cm below (in altitude) the...

I understand that this will vary from human to human, but how much weight is exerted, in total, on the average adult human body. It would be very much appreciated if the calculations can be shown. Thanks!

Writing a sci-fi story, thinking of making the alien species ammonia-based. Obviously there are problems with that. On Earth, ammonia is a liquid under cryogenic temperatures. I think -28 degree Fahrenheit is its boiling point. Obviously, this is too cold for a human to survive for very long...

Ham goes bad if you leave it there for a few days but why doesn't human body goes bad if you leave it there for a few days and when the person is alive?

I posted this in discussion because it was interesting, IMO, and does not fit anywhere on PF http://www.nature.com/nature/journal/vaop/ncurrent/full/nature17159.html Ritual human sacrifice promoted and sustained the evolution of stratified societies The hypothesis is: more use of human...

In various explanations of the event horizon which do not invoke the existence of a firewall (thereby upholding the dictum that an observer would not notice any difference upon passing the event horizon until she looked out the window), one uses the concept of a theoretical observer passing the...

Me and my friend were talking about human activities. She said that humans are creating pollution, killing so many animals creating an imbalance in food chain, global warming etc. In short we are making it worse for ourselves and other species. My reply was whatever humans do is a part of...

Particularly how can a human leap from the water like a dolphin. I'm guessing buoyancy and velocity are the main factors involved here, like a water polo ball pushed under will spring out no problem. Or a whale given enough velocity. A dolphin can dive deeper and quicker than humans and...

I'm not sure if this is the correct place to ask, but I was looking up some of the fastest vehicles in the world, with the Thrust SSC recorded to have traveled at 771 mph. On top of that many aircraft are capable of moving at speeds over 1500mph. So I was wondering how well can humans comprehed...

I have come across something that has me stumped which has something to do with the records of power output by cyclists over a one hour period. The record of the most power (watts) generated by a cyclist is in the realm of 400-500 watts for an hour, so 400-500 Wh. Now, we know that one watt...

-iation. Could the opacity of a material to one band of EM radiation (light) could be altered by irradiating the material with another band of EM radiation (X rays)? I think you are suggesting that: By raising the electrons in the atoms to higher energy bands (with the X rays), so that they will...

Artificial Intelligence Technology can be used to develop intelligent Operation systems/ Management Systems for vehicles, buildings, factories, to control various systems.. etc. We can make robots out of it... and make intelligent equipment that improves the comfort ability of our day to day...

Is the Human body capable of creating any type of frequency ? Of course vocally but beyond that ... . What devices are in existence that can measure or see frequencies of living things ? Have there been experiments with documented results that shows frequencies created by the human body ?

Are there any particles known in the Physics world with an either positive or negative charge that can be viewed by the human eye under LED light illumination and have an attraction/repulsion to magnetism?

The facts are that the person is 183cm, 82kg, meaning his center of gravity is about at 105cm, he was running towards a railing of a balcony that is 108cm high, and allegedly hit the railing then fell over. Is this physically possible?

Hello; First of all I apologize in advance if I make any wrong quotes as I am a Mech engineering and has nothing to do with biology and DNA. I wish to know the entire code or the program of the DNA structure in human brain. As I understood DNA is made up of Adenine, thymine, cytosine and...

The Biofield Energy that is also known as the electromagnetic field possessed by every human being has been used for treating human ailments since centuries. I want to know about the Quantum physics behind this and is it really possible to influence the DNA structure of a living being or atomic...

Homework Statement Hypothesize a human with a weight of: 61.14 kg (not an abnormal specimen in this wise). density of a human body: 985 kg/m^3Homework Equations What is the volume in cubic meters of such a hypothetical person? The Attempt at a Solution The mass of this person is determined...

Hello, In the picture above a couple are shown with their children. Or are they actually their children? Is it possible for them, having green (?) and hazel (?) eyes, to get 1 child with blue eyes and 3 children with brown eyes?

Homework Statement Hello! In our class, we just completed a lab on momentum and energy conservation in collisions. It was a computer simulation. Although, for the lab report, the teacher wants us to write the random, systematic, and human errors. Can someone describe what each error means? What...

The question kind of says it all. How fast fast could a human move before Relativistic mass made him collapse into a black hole(the answerer can choose whatever mass and volume that they want for the equations).

Homework Statement The activity of drugs 1 to 5 is given as follows: Drug #1: blocks RNA-dependent RNA polymerases Drug #2: blocks DNA-dependent RNA polymerases Drug #3: blocks RNA-dependent DNA polymerases Drug #4: blocks DNA-dependent DNA polymerases Drug #5: blocks ribosomes Using this...

So evolution is based on the premise that successive mutations lead to phenotypic changes ultimately resulting in varied species. This despite the fact that many mutations in nature are actually deleterious to that species. The question I have then, is that if mammalian evolution produced...

I have tried to get some answers related to a humans ability to produce power and torque on cycling forums with mixed response. So I came to the experts to help me out! Basically some cyclist belief that the maximum torque a human can produce is solely limited by their body weight keeping them...

Homework Statement The Ringling Brothers are in town and Karl decides to audition to be the human cannonball. If Jay is shot out of a cannon at 45 degrees to the horizontal with an initial speed of 25 m/s. A net is positioned at a horizontal distance of 50 m from the cannon. At what height...

It seems from what i have read that this obnoxious behavior has been happening for centuries , it is more than odorous it is a terrible habit, i for one can not stay in a room with a person that does it. And it promotes dishonesty one blaming another for the heinous act, please if you absolutely...

We humans and chimpanzees had a common ancestor from which we seem to diverge. So that indicates that the common ancestor we had at some point gave birth to an offspring which would have slightly different features or mutations. So at some point in history of the common ancestor of humans and...

Damn title character limits. I just had the weirdest thought while rearranging my computer's case fans. I put my hand in front of one of them and felt a light breeze of air, telling me it was working. This is due to the local cooling produced where the fan's airstream comes in contact with the...

Now, we humans observe time to be absolute and always progressing into entropy. However, mathematically it really just seems like a axis which helps determine energy and entropy at points along the grid. I guess what I'm curious about is if there is a bias as to how time progresses, I mean...

i have planned to make a human powered aircraft.For that i want to know about the problems on making that.

The pets many homo sapiens sapiens would just love to have: --puppies --cats --koala bears --monkeys --chickens --various birds --Polar bears (You may disagree with some of these, but that's besides the point) Theoretical physicist Dr. Michio Kaku (Yes,yes, yes...I know, not the most...

The astronauts who were traveling to the space. in what way their health were affected? During the rocket launch the spacecraft should travel greater than the Earth's escape speed. Is this speed affect the astronaut? And tell me which is the maximum speed that our human body can bear?