Connect with us

Science & Technology

Genetic ‘Adam’ and ‘Eve’ uncovered

Almost every man alive can trace his origins to one man who lived about 135,000 years ago, new research suggests. And that ancient man likely shared the planet with the mother of all women.
The findings, detailed today (Aug. 1) in the journal Science, come from the most complete analysis of the male sex chromosome, or the Y chromosome, to date. The results overturn earlier research, which suggested that men’s most recent common ancestor lived just 50,000 to 60,000 years ago.
Despite their overlap in time, ancient “Adam” and ancient “Eve” probably didn’t even live near each other, let alone mate.

“Those two people didn’t know each other,” said Melissa Wilson Sayres, a geneticist at the University of California, Berkeley, who was not involved in the study.
Researchers believe that modern humans left Africa between 60,000 and 200,000 years ago, and that the mother of all women likely emerged from East Africa. But beyond that, the details get fuzzy.
The Y chromosome is passed down identically from father to son, so mutations, or point changes, in the male sex chromosome can trace the male line back to the father of all humans. By contrast, DNA from the mitochondria, the energy powerhouse of the cell, is carried inside the egg, so only women pass it on to their children. The DNA hidden inside mitochondria, therefore, can reveal the maternal lineage to an ancient Eve.
But over time, the male chromosome gets bloated with duplicated, jumbled-up stretches of DNA, said study co-author Carlos Bustamante, a geneticist at Stanford University in California. As a result, piecing together fragments of DNA from gene sequencing was like trying to assemble a puzzle without the image on the box top, making thorough analysis difficult.
Bustamante and his colleagues assembled a much bigger piece of the puzzle by sequencing the entire genome of the Y chromosome for 69 men from seven global populations, from African San Bushmen to the Yakut of Siberia.
By assuming a mutation rate anchored to archaeological events (such as the migration of people across the Bering Strait), the team concluded that all males in their global sample shared a single male ancestor in Africa roughly 125,000 to 156,000 years ago.
In addition, mitochondrial DNA from the men, as well as similar samples from 24 women, revealed that all women on the planet trace back to a mitochondrial Eve, who lived in Africa between 99,000 and 148,000 years ago  –  almost the same time period during which the Y-chromosome Adam lived.
But the results, though fascinating, are just part of the story, said Michael Hammer, an evolutionary geneticist at the University of Arizona who was not involved in the study.
A separate study in the same issue of the journal Science found that men shared a common ancestor between 180,000 and 200,000 years ago.
And in a study detailed in March in the American Journal of Human Genetics, Hammer’s group showed that several men in Africa have unique, divergent Y chromosomes that trace back to an even more ancient man who lived between 237,000 and 581,000 years ago.
“It doesn’t even fit on the family tree that the Bustamante lab has constructed  –  It’s older,” Hammer told LiveScience.
Gene studies always rely on a sample of DNA and, therefore, provide an incomplete picture of human history. For instance, Hammer’s group sampled a different group of men than Bustamante’s lab did, leading to different estimates of how old common ancestors really are.
Adam and Eve?
These primeval people aren’t parallel to the biblical Adam and Eve. They weren’t the first modern humans on the planet, but instead just the two out of thousands of people alive at the time with unbroken male or female lineages that continue on today.
The rest of the human genome contains tiny snippets of DNA from many other ancestors  –  they just don’t show up in mitochondrial or Y-chromosome DNA, Hammer said. (For instance, if an ancient woman had only sons, then her mitochondrial DNA would disappear, even though the son would pass on a quarter of her DNA via the rest of his genome.)
As a follow-up, Bustamante’s lab is sequencing Y chromosomes from nearly 2,000 other men. Those data could help pinpoint precisely where in Africa these ancient humans lived.
“It’s very exciting,” Wilson Sayres told LiveScience. “As we get more populations across the world, we can start to understand exactly where we came from physically.”

Source

Comments

Science & Technology

Japan has developed an inflatable scooter that weighs practically nothing

The University of Tokyo engineers have developed the Poimo inflatable electric scooter, which is created individually for each owner. It is enough to send your photo to the manufacturers – and a personal optimized model will be assembled for you.

The scooter is designed with a special program for the body size of a particular user and his specific fit. Moreover, each owner is free to make any changes to this model. If he makes any changes to the drawing, the program will automatically redesign the electric bike to maintain its strength, stability and controllability. When the model is finished and approved, it is handed over to the manufacturer.

Scooter Poimo

The scooter consists of seven separate inflatable sections that are constructed from durable fabric and sewn with straight stitch. It remains to add electronic components – in particular, a brushless motor and a lithium-ion battery. 

The finished electric scooter weighs about 9 kg and can travel at speeds up to 6 km / h (that is, slightly faster than a pedestrian). It can work for an hour on one charge.

This is how the current version of Poimo looks like in action:

Continue Reading

Science & Technology

Excerpts from Elon Musk’s speech at the Martian Society convention

Elon Musk’s comments with questions relayed from the Mars Society Membership by Dr. Robert Zubrin, James L. Burk, and Carie Fay. Following Elon’s 30 min time, Dr. Zubrin took additional questions. This special event was part of the 2020 Mars Society Virtual Convention from October 14-18, 2020.

About Starship Test Schedule:

– entering orbit – with a probability of 80% -90% will take place in 2021

– the probability of the return of the ship and the 1st stage in this flight is 50%

– test of refueling in orbit – 2022

– Starship lunar version – 2022 or 2023

– Starship flight to Mars – around 2024

The goal of the Starship is to build a self-sufficient settlement on Mars as quickly as possible. Musk does not rule out the possibility that this will not be achieved during his lifetime. According to his rough estimates, to create a self-sufficient city, it will be necessary to deliver 1 million tons of cargo, which corresponds to 4-5 million tons in a low Earth orbit. Modern single-use launch vehicles are capable of removing less than 1% of this value.

“Disposable launch vehicles are completely stupid. They are a waste of time. I think people need to stop wasting time on this. If you try to sell a disposable plane, you will be thrown out of the office. If you try to sell a disposable car, you will also be thrown out of the office. “

A series of questions and answers followed:

What is the best landing site on Mars?

– I’m not sure about that. But I can name the criteria. The first of these is latitude: most likely it will be in the northern hemisphere, far enough to the north to have water ice, but to still have enough sunlight.It also needs to be low to get the most benefit from atmospheric braking.

How do you prioritize mission priorities: research, infrastructure construction, and science?

– The first will be the construction of a fuel plant.

A question from a teenager who wants to become an engineer and robot maker with a dream to work at SpaceX: what is the most important education in order to become an engineer?

– There are many varieties of this profession: you can be an aerospace engineer, in the field of electronics, software, or a chemical engineer involved in creating safe production of fuels. I think physics is a good foundation for critical thinking.

Boring Company was originally conceived as a tunnel manufacturing firm on Mars?

– No. It was originally something of a joke. I thought tunnels were a good solution to reduce the traffic problem in cities and improve the quality of life by turning parking lots into green parks. To do this, you need to go to 3d [get away from the “flat” infrastructure – approx. per.]. I think tunnels are good for Mars too. But there you need a lot lighter equipment: you don’t care about mass on Earth, but you will have to take care of it a lot when going to Mars.

At Boring Company, have you learned a lot of technology that might come in handy on Mars?

– I think, yes.

Do you have any tips for young people who love Mars but don’t know how to participate in its settlement?

– I think any strong advocate of the need to conquer Mars matters. People often don’t even think about it. I often talk to people who don’t even know about it. Therefore, I consider it important for humanity and consciousness in general to bring a discussion about this to society. Talking about it with friends and acquaintances – I think this is what we should do. In my estimate, we will spend less than 1% of our efforts on Mars exploration, exactly less than healthcare, perhaps even less than cosmetics – this will be enough to make life multi-planetary. But this requires people to start talking about it 100 times more often. I think this is what really matters. [the entire cosmonautics of the world is $ 424 billion a year, while cosmetics is $ 532 billion, and tobacco production is $ 849 billion – approx. per.]

What’s the coolest part about Starship development?

– I think the coolest detail is the ability to work with a great group of engineers and come up with interesting solutions. I think the best thing is the opportunity to work with smart and creative people who come up with solutions that were not available before. This is a great reward.

What do you focus on when hiring, especially with regard to engineers?

“We’re looking for signs of exceptional ability. Or at the very least, striving to do exceptional things at SpaceX.

Are you planning to make a Mars-Earth communication system like Starlink?

– Yes, I think we will use a laser, probably launched into orbit, to avoid atmospheric diffraction. Thus, it will be a laser beam going from the orbit of the Earth to the orbit of Mars. And also relay satellites in solar orbit, since the laser beam cannot be sent through the Sun [when it is between Mars and Earth – approx. per.].

Can Starship be used for other destinations like Venus and other planets?

– Starship will be able to travel to any target in the solar system that has a solid surface when fuel depots appear. It is not the kind of transport that will take us to other stars, but when we become a multi-planetary species, we will create a demand for innovation in space travel that will ultimately lead us to interstellar travel.

Continue Reading

Science & Technology

Cern Scientists Plan an Impressive Experiment – They Will Come Into A Parallel Universe

Cern scientists are once again preparing to impress the entire planet and become the focus of discussions with the new experiment they are planning.

An experiment that, if it brings the fascinating result that scientists have in mind,  will change the way we think about the world , will take place in the next few days at the Large Hadron Collider, the European nuclear center, Geneva CERN Research.

The astonishingly LHC complex, the largest, most energetic elemental accelerator in the world,  will be “fired” for the first time to its highest energy levels, in an effort to detect – or even create – tiny black holes. 

If it succeeds, then, a completely new universe will be revealed – rewriting not only the books of physics, but also the books of philosophy! 

It is possible, however,  that gravity from our universe will “leak” into this parallel universe, as LHC scientists say. 

From the Higgs boson to dark matter and the parallel universe

According to the British Express, the experiment is sure to “trigger” the critics, who are worried about the LHC, many of whom warn that the elementary particle accelerator will mark the end of our universe, creating a of the black hole.

Nevertheless,  Geneva has remained … intact since 2008, when the LHC began its spectacular “work”.

The first scientists at the Large Hadron Collider proved the existence of the Higgs boson – a key building block of the universe – and the LHC appears to be on track to locate “dark matter” – a previously undetectable force now considered that it constitutes the majority of matter in the universe, being, in fact, the reason why the latter is constantly expanding and moving away. 

So next week’s experiment is considered to change the game. 

The truth is out there

Mir Faizal, one of three heads of the three natural groups behind the experiment, said: 

“Like many parallel sheets, which are two-dimensional objects (width and length) can exist in a third dimension (height) , so parallel universes can also exist in higher dimensions. We anticipate that gravity can leak into extra dimensions, and if that happens, then tiny black holes can be produced in the LHC. 

Normally, when people think of the multiverse, they think of the interpretation of quantum mechanics by many worlds, where every possibility is realized. This cannot be tested and so it is a philosophy and not a science. We do not mean this with parallel universes. What we mean is real universes, in extra dimensions. The truth is out there.”

Continue Reading
Advertisement

DO NOT MISS

Trending