A Family Tree with over 27 Million Ancestors has Been Discovered

 

A Smithsonian article that was just published announced that the largest family tree has been discovered, and it contains over 27 million ancestors. By using genomes from ancient ancestors as well as modern genomes, scientists were able to reconstruct the tree based on geographic location. Because there were many difficulties for researchers to be able to decipher how to combine different genome sequences from multiple databases, this newly developed study has changed the world of genetics.

The study, primarily conducted by Anthony Wilder Wohns, discusses the methods and results from constructing the tree, as well as the difficulties going into working on this research. The introduction mentions how diverse genomic datasets are and working with several of those datasets can cause errors when dealing with complex patterns. 

The results of the study were successful in terms of the intention of the study. They were able to used over 3000 modern genomes and a few ancient ancestor genomic sequences to compile 27 million haplotype fragments as well as over 200 million ancestral lineages. By using the ancient samples, researchers were successful in identifying individuals as well as populations which created lines of descendants. They were also able to use geographic location discussing evolution and the out-of-Africa theory, which describes that the earliest humans came from the African continent, and eventually spread out over time. To conclude the study, researchers wrote that this is a great start to investigating genomic sequences and discovering more information about evolution, specifically in humans.

While the study was successful and provides key information in the world of evolution and genetics, there is still a lot of additional research to be done. The tree suggests that earlier humans may have come to North and South America earlier than expected, as well as similar interesting information about Oceania humans. The scientists who worked on this discovery intend to use it to help other areas of science, like in the medical field. 

When I saw this article, I was immediately drawn to it because of how many ancestors the researchers were able to connect. The world of technology and its work in genetics is remarkable and the idea that we can use geography and genomic sequences to help understand evolution and our lineage is amazing. Since this is fairly new, I expect more information to arise in the coming weeks as more researchers analyze the results seen in the study. I hope that this leads to more discovery in terms of the biological studies and that we can learn a lot of valuable information about our past.

Related Articles:

More Information Regarding the Study

Earlier Research Using Genetic Sequencing to Construct a Family Tree

A new book captures how genetics fills in the story of life’s evolution

 

Not many people have really explored how life became to start on land, this article explores that of which organisms started to come on land. When descendants of ancient fish started to come onto land they didn’t have any lungs. The study shows the gene in fish that need swim bladders which is the organ in a fish to help it control its buoyancy, are the same organ that lungfish and humans use to build lungs. Genetic mutations can trigger the production of new proteins, which can serve as a new function or perform the old function better in which will enhance the organism's survival. Mutations cause genes to be expressed or not, later in development in different places in the embryo. It can alter the form of the skulls,fins, limbs, and other anatomical body parts. These genes usually arise by duplication a process of making a gene that retains the original function but frees the other copy to change. This article was interesting because it's true that we don’t genuinely think of how we got to be on land and not in water. In which there are alot of theories about how we did end up on land, however the most prevalent one is us evolving from fish essentially.

The Bigger the Nostril, the Hotter the Air

It has been found through a study by a team of scientists from Pennsylvania State University that the shape of one’s nostril may share a relationship with the climate of the region that that person’s ancestors descended from. While noses are used for smelling, they are also used to warm and humidify the air that we breathe. It had been found that the more narrow the nostril, the more efficient the nose would be at warming and humidifying the air. Thus, people that descend from colder climates have more narrow nostrils, as they need noses that are more efficient at warming the cold air, and people that descend from warmer climates have wider nostrils, as they do not need noses that are as efficient at warming the already-warm air. It is stated, however, that the climates of past ancestors’ regions are not deciding factors on nose width; other genes may come into play that affect the shape of one’s nose. 

I love studies that center around the morphology of humans, so of course I was very interested reading this article. Reading articles that center around humans evolving to have advantageous traits is so interesting to me because I love to think that there are some humans out there that for some reason have higher-functioning noses than I do. It intrigues me that a larger-nostriled friend might have an easier time breathing in the Canadian wilderness than I would, simply because of the morphology of their nose. The study does make sense, anyhow, that humans in colder regions would evolve to breathe easier, and humans in warmer climates would evolve as to not have noses that are too efficient at heating already-warm air. It makes sense that someone like myself, who descends from a tropical country like the Philippines, has such large nostrils. 

Why do we kill? Controversial study blames our distant ancestors

Recently, an experiment was conducted by José Gomez, Evolutionary Biologist at the University of Granada, to determine whether or not lethal violence was something that specific species of animals were predisposed to due to ancestors and evolutionary reasons, or if it was something they acquired individually.
Data from over one-thousand different species was collected to gain further insight into how many of these animals were killed by a member of the same species. A pattern emerged between animals that lived in groups and animals that lived on their own, showing that territorial group animals displayed higher incidents of lethal violence than animals that slightly isolated themselves from others of the same species.

Scientists then concluded that the more violent the species' ancestor was, the higher the chance of that species being lethally violent. According to the lethal violent rates in human ancestors, chimps, and bonobos, it was predicted that 2% of human deaths would be caused by other humans. Since primates live in groups that have a history of violence, the human rate of lethal violence was calculated using records from 50,000-10,000 years ago (hunter-gatherer time) and compared them to today's data. The percentage climbed to 12% as human settlements evolved and culture influenced violence.
Scientists not being able to clearly differentiate types of lethal violence when comparing species, as well as gathering a sufficient amount of data, created a hurdle in the experiment and the margin of error was taken into consideration by workers, with the intention of diving into more species in the future. The addition of more species, strengthens the validity of data and can aid in gathering a more solidified correlation. Identifying a correlation in behavior  of animals through genetics is an essential factor in gaining an understanding of the human race in relation to evolution and why humans do what they do.
http://www.sciencemag.org/news/2016/09/why-do-we-kill-controversial-study-blames-our-distant-ancestors

How did we get where we are now?

Where do you think your ancestors came from? Well, it is finally concluded that even if you're not from African descent, your ancestors most likely did in fact come from Africa. We all have ancestry from people who lived in Africa 50,000-80,000 years ago!
It is well known that humans evolved in Africa roughly 200,000 years ago. But how did they disperse and colonize different lands? This is the question that three different teams of researchers began to study. In order to fully understand human history, geneticists sequenced genomes of 787 people from indigenous populations like Basques, Mayans and Cree Indians. Although early studies of DNA draw conclusions that all non-Africans are all closely related, the main question the geneticists had was how humans expanded and spread from Africa.

A single strand of hair, about a century old, gave the answer partially away. With this single strand of hair, Dr. Willerslev and his team reconstructed the genome of an Aboriginal Australian. This info was enough to give away the fact that the ancestors of Aboriginal Australians arrived about 62,000 years ago in East Asia when they descended away from other non-Africans. After all three studies were done, the teams gathered enough information from sequencing the genomes of people from different indigenous populations  to conclude that ancestors of non-Africans split off about 65,000 to 200,000 years ago! Although their is a vast time difference, they concluded that the reason for humans leaving Africa in the first place was due to the rapidly changing climate, rainfall in particular. Humans followed the tracks of the rainfall into early Eurasia where their would be better sources of food. Therefore, next time you want insight into where your early ancestors came from, keep in mind that they all came in different waves from Africa to migrate towards different lands!

Some Cultures Hardwired for Vegetarian Diet

         An article from Discovery News talks about how some people have adapted to vegetarian diets better than others. I personally love to eat meat and found this article interesting to read. Based on what their ancestors ate, people have more of a tolerance for meat in certain areas compared to others. My family is from the Mediterranean and Europe. I do not have a lot of family from northern Europe where their culture has adjusted to the vegetarian diet and evolved the genetic mutation known as rs66698963. Honestly, I’m happy I am not from areas where the mutation have evolved because I cannot imagine not being able to eat a nice steak or a burger in the summer. 

         I think it is so fascinating that genes can vary so much depending where you are from. Genes from people from other states in America alone vary so much alone that thinking at a larger scale and comparing individuals from other countries baffles my mind. The mutation has such an affect that if individuals with the mutation stray from their vegetarian diets, they could have a higher risk than others for heart disease, colon cancer, and a variety of additional health problems associated with inflammation. But also think about this: if what your ancestors at affects your genes and your lifestyle now, how can your lifestyle affect the generations after you?

Here is another article about cultural differences in vegetarianism. 

Study Finds Surprising Benefit of Viral DNA: Fighting Other Viruses

Yet as foreign as viruses may seem, the boundary between them and us is turning out to be remarkably blurry. We use DNA from viruses to do things that are essential to our own survival, scientists are finding. Somehow, we have managed to domesticate some of these invaders.

Endogenous retroviruses first invaded the cells of our primate ancestors more than 50 million years ago. Scientists have identified over 100,000 of these fragments in the human genome, accounting for 8 percent of our

DNA.

To fight invading viruses, a cell needs to turn on many genes at once. The genetic switches that make this possible are stretches of DNA next to each gene, which are themselves activated by proteins.

The scientists edited the DNA of human cells they grew in a dish, chopping out some of the viral switches near interferon-responsive genes. Then they exposed those cells to interferon. The immunity genes, they found, barely woke up.

Original Article:http://www.nytimes.com/2016/03/03/science/study-finds-surprising-benefit-of-viral-dna-fighting-other-viruses.html?rref=collection%2Fsectioncollection%2Fscience&action=click&contentCollection=science&region=stream&module=stream_unit&version=search&contentPlacement=10&pgtype=sectionfront

Our closest wormy cousins: About 70% of our genes trace their ancestry back to the acorn worm

A team from the Okinawa Institute of Science and Technology Graduate University (OIST) has recently sequenced the genomes of two species of acorn worms and have found we humans share more genes with them that we do with many other animals, showing they are our distant cousins. Around 550 million years ago, a variety of animals were born into the world in an event called the Cambrian explosion. This event revealed several new animal body plans and introduced complex animals with specialized huts and behavioral features, including the deuterostome family. Through genome sequencing of several contemporary animals in this family we are capable of going back in time to unveil aspects of the long-lost ancestor of deuterostomes. One of the animals to come from this ancestor is the acorn worm, which is a marine creature that lives on the ocean floor and feeds by filtering a flow of sea water thought tiny slits in their gut region between their mouth and esophagus. These slits are distantly related to the gills of fish, and represent a critical development in evolution. Because acorn fish have such a critical evolutionary development the researchers sequenced two acorn worm species, including Ptychodera flava of Hawaii and the Saccoglossus kowalevskii found in the Atlantic Ocean. The team was interested in identifying ancient gene families that are present in the deuterostome ancestor, and thus compared the genomes of the two worms with the genomes of 32 diverse animals.

The study found that all deuterostomes share 8,600 families of genes, and that approximately 14,000 or about 70% of our genes trace their ancestry back to the original deuterostomes. By comparing the genomes of the acorn worm to other animals the group of researchers found the presence of these genes in the common ancestor of all the deuterostomes, which is a now extinct animal that live half a billion years ago. The study showed that the pharyngeal gene cluster, which forms the slit in the acorn worm, is a characteristic unique to the deuterostome family and could be linked to the development of the pharynx in the humans, which is the regions that links the mouth and nose to the esophagus.

The gene cluster was found to only exist in deuterostomes and is not found in non-deuterostomes. The gene cluster contains six genes ordered in a common pattern, that includes the genes for four proteins that are crucial transcription regulators that control the activation of numerous other genes. The DNA that codes for these genes, as well as some of the DNA pieces that are used as binding site for the transcriptions factors is shared and conserved among all deuterostomes.

I find this article extremely interesting because it shows how genetics and our genes can be used in the concept of evolution. The fact that we can trace our genes back billions of years and find common ancestors of modern day animals that are so different is extraordinary. It really shows the power of genetics and shows how our genetics can be so similar yet small changes can drastically change our development.

For a link to the original article click here
For more information about this discovery click here
To learn more about the acorn worm click here

A New Ancestor

Recently, in South Africa, a new human relative fossil was dug up, which suggests a new point of view of the evolution of mankind.  The relative, named Homo naledi, was surprisingly more complete, and intact, than most relatives, suggesting that Homo naledi is mankind's closest ancient relative.  This idea of a whole new path of evolution, doesn't exactly excite all pathologists.

With a whole new species thrown into the mix, it "changes the human story."  The features of this new found species includes, the already discovered, bipedalism, high intelligence and herbivore-ish diets; as well as some new features such as an ape-sized brain, but Homo-like feet and teeth.  For those pathologist who are not in denial, they believe that Homo naledi just aids in proving that the human genome evolved from multiple different Homo species, creating this very diverse world in which we live in today; and that our ancestry is a "tangle of branches" on the phylogenic tree of life.

I found this article highly interesting, especially since my last semester Biology class spoke of phylogeny and how it is all a big guessing game.  Every time a new species, or ancestor, is introduced, there is no single right or wrong answer as to who should be placed where.  However, sometimes when a wrench, like this, is thrown into the mix, we may need to take a step back and do some rearranging.

Your Ancestors, Your Fate

   

     In this article, Your Ancestors, Your Fate, it talks about how social mobility has not changed much over the years despite the fact that society thinks it has. A study conducted by researchers at Harvard and Berkeley suggest that social mobility hasn't slowed but has always been slow. This fact seems to be consistent across different nationalities and sociopolitical systems. The recent study suggests that you can predict your social status based on the lineage of your family and that it takes somewhere between 10-15 generations for a families status to merge towards the mean (high status families fall and low status families rise). This conclusion comes from examining data of surnames across the globe. The article provides examinations of several different countries with similar conclusions to include; Chile, China, England, India, Japan, South Korea, Sweden and the United States.The article also talks about how adoption and siblings studies show that biological factors are the main determinant of social status. Due to the aforementioned factors in this article, the authors than talk about how "policies to lift up the lives of the disadvantaged" should be enacted.
     I am not sure how I feel about the findings in this article. Sure, it is more likely if your family is rich you will be rich and vice versa. However, the point that we should push public policies "to lift up the lives of the disadvantaged" is controversial to me. At some point public policies to lift up the disadvantaged will pull down the so-called "privileged" in possibly an unfair manner. The article concludes by saying "What governments can do is ameliorate the effects of life’s inherent unfairness" and I think we can all agree on that but how this is done "fairly" is a much more difficult task, in my opinion.
     For more on the subject of social mobility see the link http://www.verisi.com/resources/prosperity-upward-mobility.htm

Root of Ashkenazi Family Tree

    The origin of an important Jewish population, the Ashkenazim of Central and Eastern Europe has forever been a mystery. A new genetic analysis has been configured, pointing to European women as the female founders, and the Jewish community of the early Roman empire as a source of the Ashkenazi ancestors. In previous studies it was told that the women who founded the Ashkenazi Jewish community were from the Near East, but today's findings express otherwise. A study led by Martin B. Richards of the University of Huddersfield, England, composed a genetic analysis of maternal lineages. The team analyzed the Ashkenazi lineages by decoding the mitochondrial genomes of people from Europe and the Near East. Earlier DNA studies showed that Jewish communities had been founded by men whose Y chromosomes bore DNA patterns found in the Near East. But, unlike the males, when geneticists went to examine the females, their mitochondrial DNA has no common pattern. In the smaller communities it resembled that of the surrounding population, suggesting a migration pattern in which the men arrived single, possibly as traders, and took local wives who converted them to Judaism. But this idea has not been clear as to if this is true or not of the Ashkenazim.
    A 2006 study reported that the four most common mitochondrial lineages among the Ashkenazis came from the Near East, implying that only four Jewish women made up the entire ancestry of about half of today's Ashkenazim. But at the time decoding DNA was expensive and those scientists only analyzed a short length of the DNA. However, in this New York Times article Dr. Richards was able to draw up the Ashkenazi family tree with much finer resolution and more accuracy. His trees showed that the four major Ashkenazi lineages form clusters within descent lines established in Europe between 10,000 and 20,000 years ago. In conclusion, he determined that "at least 80 percent of Ashkenazi maternal ancestry comes from women indigenous to Europe, and 8 percent from the Near East, with the rest uncertain." Richards feels that the four major lineages became incorporated into the Ashkenazi community about 2,000 years ago because at that time a large Jewish community was flourishing in Rome and included many converts. A recent analysis of whole genomes of Jewish communities was noted that almost all overlap with non-Jewish populations. Overall, Richards sees this knowledge as a possible time and place at which the four European lineages could have possibly entered the Jewish community, becoming numerous later as the Ashkenazi population in northern Europe expanded from 25,000 in 1300 A.D., to over 85,000 million in the beginning of the 20th century.

I chose this article to read because I love learning about ancestry. This discovery caught my eye and I feel that new findings in ancestry offer many answers to many questions people may ask. We want to know where we come from and the more we know the more we can express to others.

(Article): http://www.nytimes.com/2013/10/09/science/ashkenazi-origins-may-be-with-european-women-study-finds.html?_r=0


Second Link: http://blog.23andme.com/23andme-customer-stories/ashkenazi-and-me-discovering-unknown-jewish-ancestry-with-23andme/