Analysis of the organism genome to re-establish the evolutionary tree

Researching the largest bird genome so far is not only surprising but also completely changes their evolutionary tree. The study challenged the current classification system, changing our understanding of bird evolution, and providing invaluable information for other phylogenetic or comparative studies.
> The pairs of idea birds are different

Birds are among the most loved and well-studied species, based on studies of them that we know about animal biology, from natural history to ecology, good species formation. reproduction . It is all based on information from birds. However, their life tree is still a highly controversial, elusive problem so far.

During the past five years, the Early Bird Assembling Tree-of-Life Research project, conducted at the Field Museum, has been analyzing DNA from all of the existing large bird species. now on. Until now, scientists have established and analyzed information of more than 32 kilobytes from 19 different locations on the DNA sequence of 169 bird species. The result of this massive study is equivalent to a small genome research project published in the June 27 issue of Science.

Shannon Hackett - one of the three main authors of the study and manager at Field Museum - said: 'Our research with new insights - has significant implications for the evolutionary relationship of birds - the discovery is due to technological advances in recent years; enabling us to sample a much larger proportion of genomes. The study has yielded significant results and demonstrated the ability to collect genomic data to reconstruct an evolutionary tree '.

Eagle.When it comes to birds, looks can trick us.For example, the new study, published in the June 27, 2008 issue of Science, has determined that falcons are not as closely related to hawks or eagles as we previously thought.(Photo: Stephanie Ware, courtesy of The Field Museum)

The results of the study are so wide that the scientific names of dozens of bird species are forced to change. Biological books as well as guidelines for observers of bird identification must also be edited. For example, we now know that:

Birds adapt to diverse environments through different stages because many species of birds that live on water (such as flamingos, tropical seabirds or diving birds) do not evolve from one group of other waterbirds. Many species that live on land (such as turaco birds, pigeons, sand grouper and cuckoo birds) have not evolved from a group of other shallow birds.

Similarly, typical lifestyles (such as nightlife, meat eating, living near the sea, living on the sea or large seas, for example) have also evolved several times. Contrary to popular belief, day-to-day hummingbirds have brilliant outfits that evolve from night-brown mosquitoes that work at night. The eagle is not closely related to hawks or eagles. Tropical seabirds (white seabirds, very fast flying birds) are also not close relatives to pelicans or other waterbirds.

The shore-based birds are also not the basic evolutionary group, which rejects the widespread view that terrestrial birds have thrived today.

Sushma Reddy - another author of the study and a postdoctoral researcher at Field Museum - said: 'With this study, we learned two important things. First, looks may be fooling us. Birds that look alike or similar to each other are not necessarily relatives. Secondly, most of the classification of ornithology as well as common knowledge about the evolutionary relationship between ores is not correct. '

Evolution of birds

To understand the evolution of birds is extremely difficult work. Perhaps because the current birds are relatively fast (within a few million years) after a radiation eruption occurred about 65 million years to 100 million years ago. The result of the rapid decomposition process at the beginning of the evolutionary history of the main bird is that many groups of birds with the same appearance (such as owls, parrots or pigeons) have little or almost no The intermediate form links them to other groups of birds with a clearer basis. This makes it difficult to identify some related evolutionary groups.

Many previous studies of bird evolution have only resulted in conflicting results. This new study, however, is the most massive study by unprecedented large sequences of genetic sequences. The team analyzed about 32 kilobytes of genetic information in each species, the data volume was about five times larger than any previous study. Besides, the data is analyzed using different methods and programs.

Rebecca Kimball - the third lead author of the study and associate professor of zoology at the University of Florida, Gainesville - said: 'Unlike previous studies, we have discovered a number of division groups. basically in Neoaves with some supportive evidence (this is a basic group of ornithists that account for 95% of the current bird population), this sign is also stable throughout other studies'.

The co-authors of the study included scientists at the University of California, Berkeley, Smithsonian Institution, Stellenbosch University (South Africa), University of Maryland, Louisiana State University, Wayne State University, and New State University. Mexico. More than half of the collaborating or training members in the study are women.

At the Field Museum, most DNA analysis and sequencing tests were conducted at the Pritzker Evolution and molecular laboratory. The laboratory was established in 1974 to study genetics and research to conserve biodiversity in the world. Since 2000, over 190 scientists from 29 countries have been trained here. Currently, more than 60 projects are underway in the Pritzker laboratory, studying everything from sharks to plants and lichens, from owls to flamingos. Just last month, the Field Museum opened Daniel F. DNA Discovery Center and Ada L. Rice to create a community face for the lab. The new center allows visitors to observe laboratory activities such as observing DNA extraction, sequencing and analysis for a number of projects, including projects. Early Bird. Besides, visitors can also talk to scientists at a limited number of times during their working time.

In addition to visiting the area, the 1,850-square-foot DNA Discovery Center is also equipped with videos, hand-held interactive devices and informational symbols. The center intends to open an adult exhibition with students from middle school and above. Located on a balcony overlooking Stanley Field hall, the DNA Discovery Center offers free admission.

In the United States alone, there are about 82 million bird observers, making this the second most popular hobby after gardening in the United States. Therefore, the interest and results of the Early Bird project will be much more influential.

Reddy said: 'We now have a huge evolutionary tree from which to study the evolution of birds and all their interesting properties that have attracted many scientists and people. amateur for centuries. Birds have a great diversity of species (they are the most numerous group of four genera). Using the genealogical tree we can begin to understand where this diversity comes from as well as how the link between the groups of oranges takes place '.