Hundreds of new genomes help fill the bird tree of life

 

On this planet, there are more than 10,000 bird species. Recently, scientists have gained a better understanding about these feathered animals and the evolution behind them. This new found knowledge came about when a international team of researchers released the genetic instruction books of 363 species of birds. Within this book was 267 genomes that were assembled for the first time ever. Scientists were then able to use this new data to figure out the varied traits of birds like adaptions for flight, etc. 

Researchers then took the DNA from bird tissue samples from 17 scientific collections that span across the world. This data was around 92 percent of all modern bird families including chickens and even a rare species like the Henderson crake. Ornithologist Michael Braun of the Smithsonian National Museum of Natural History stated Braun says that the "data can be used better understand everything from the parallel evolution of flightlessness in ratites like emus and kiwis to the evolution of vision and song learning in birds overall". Researchers have already found peculiarities in some of the genomes and don't plan to stop assembling and releasing genomes until ever species is included.

I think this is a great advancement dealing with the evolutionary history of birds. I hope that more genomes are discovered so that we can have a better understanding of the bird tree of life and all the different traits they have. I also would like to learn more about birds in general and all the different types there are.

Links: 

https://www.sciencenews.org/article/birds-species-genomes-tree-of-life

https://www.nature.com/news/tree-of-life-constructed-for-all-living-bird-species-1.11712

Tree of Life's New Look

The tree of life was first thought of in 1859 when Charles Darwin wrote “On the Origin of Species”, since than the tree of life has been studied and referenced, theoretically that is. The invention of DNA sequencing was first to change the way scientist theorized the tree of life. This was because DNA sequencing let scientist find the relationship between species through their genes. It was not until 1970 when Carl Woese of the University of Illinois and his colleagues first published a “universal tree of life”, which was presented with the three main trunks we all know, eukaryotes, bacteria, and archaea. When scientist wanted to add new species to the tree they faced a challenge because they did not know how to grow many of the single celled organisms in the lab. Researchers however, developed a way to conquer this challenge, by pulling pieces of DNA from the environment and piecing them together.

Jillian F. Banfield of the University of California, Berkeley and her colleagues have been using the DNA piecing together technique for awhile now and have assembled genomes of hundreds of microbial species. The problem now was to figure out where they fit into the tree of life. Their solution was to redraw the tree. This was done by selecting more than 3,000 species to study, which gave them a large enough sample of diversity, and studied DNA form 2,072 known species along with DNA from 1,011 species of newly discovered. With their new data they used a supercomputer to evaluate the possible number of new trees. They eventually found the one that best supported their evidence, which is the one presented today. With the new tree it shows how much bacteria have been over showed by the close relationship between eukaryotes and archaea.

This new tree can present new questions for scientists and brings a whole new look at life’s evolution. I never thought I would see something that has been looked at and taught the same for so many years. I grew up with almost all of my science classes presenting the same tree and giving the same evidence, but now there is a new perspective.

New 'Tree of Life' Diagram

A team of scientists have recently recreated the "Tree of Life" diagram. They extended the amount of organisms primarily under the bacteria branch because they have found such a vast amount in mud of meadow-lands. They pulled pieces of their DNA to be analyzed through a separated that separated each entry to create the new diagram. The new tree has a thinner branch for eukaryotes with archaeabacteria being shown as having a closer relationship between the two. They have selected 3,000 species to be on this new tree with over 1,000 being newly discovered species. However there is speculation that some of these species could be chimera which would have a mixture of DNA from more than one organism. There is also the debate of whether the bacteria branch has begun to plateau or if there is an astoundingly larger amount out to still be discovered.

Aesthetically, the tree looks a lot more interesting than what Darwin's original "Tree of Life" from his 1859 book "On the Origin of Species". There is so much more to the new diagram, and it gives a better idea of how vast the amount of bacteria there are especially in comparison to eukaryotes such as mammals. I believe that there are more bacteria to be discovered that will only belittle the amount currently depicted. With the advancement of technology discovering new species should be simple. I do find it peculiar how archaeabacteria is actually more closely related to eukaryotes as opposed to bacteria. Archaeabacteria seem like very simple organisms that do not have the same complexity of eukaryotes.

Figure 1. New "Tree of Life" Diagram.

Figure 2. Darwin's Original "Tree of Life" Diagram

Scientists map 1,000 molecular tools common to cells across tree of life

One of the largest experiments ever undertaken by seven research groups in three different countries into animal molecular biology has found that across the tree of life many organisms share protein machines that help cells to function. The tests were done on a range of organisms from slime mold, yeast, worms, to sea urchins, sea anemones and flies, mice, and even humans. The new study identified instructions for almost 1,000 protein complexes that were found across the tree of life.

I think this article is interesting because scientist have found over the years many ways that different organisms or similar and different but not too many ways that all organisms are linked. Knowing that we all share proteins for cell function can hopefully progress different studies in science.

original link

Related article (This research can be applied to many studies)

Part Human, Part Plant?

            Although we all present the physical characteristics of humans, a new study has shown that human DNA may be composed of over 145 genes that originated from organisms such as plants and bacteria. Horizontal gene transfer, is a way in which bacteria exchange genetic information with neighboring microorganisms. This is commonly used to allow organisms to acquire resistance. Although this concept is not fairly new, studies reveal that this mechanism may have played a role in human evolution. The article illustrates that while many believe the tree of life is clear and displays the lineages of organisms through generations, it may be much more messy and tangled than we originally believed.

            Biologists from the University of Cambridge sequenced the genomes of 40 different organisms and species, and compared their DNA to that of humans. One hundred and forty five genes are believed to have originated from simpler bacteria's, with seventeen genes that may have been transferred through horizontal gene transfer. The researchers have identified the functions of these genes in our bodies, but they are still investigating the time period in which these genes may have been transferred and the circumstances which may have lead to this.

            This discovery can change everything we believe to know about evolution. The origin of man is often debated in the scientific community, and these studies can provide us with a clue as to where humans have developed from. The article shows that there are many who believe in an alternative explanation for these genes. One possibility suggested by Johnathan Eisen, microbiologist from UC Davis, is that while horizontal gene transfer is a possibility, it is also possible that these genes were passed through by a distant relative that was lost in some generations.

Original Article: http://news.sciencemag.org/biology/2015/03/humans-may-harbor-more-100-genes-other-organisms

Secondary Article: http://amrls.cvm.msu.edu/microbiology/molecular-basis-for-antimicrobial-resistance/acquired-resistance/acquisition-of-antimicrobial-resistance-via-horizontal-gene-transfer