Biology Today: DNA, Plant and Animal Evolution, Population Growth

DNA in Forensic Science

Biology is a system of wildlife and natural sciences. Biology is extremely important in human life. With the help of this science, people are able to study the process of their evolution and evolution of animals. Life sciences have become the main priority of modern society. Not only scientists but also politicians and the general public pay very special attention to the questions of biological diversity and climate changes. The purpose of the paper is to study such questions in forensic science as DNA, population evolution and microbial life, biological diversity evolution, plant and animal evolution, population growth, biomes, and ecosystems.

Biology has for a long time occupied its honorable place among other disciplines, including criminology. The implementation of biological methods of analysis in the forensic examination process has a very long history. For example, initially, there was serological typing of molecules in biological fluids, such as markers of blood groups, as well as certain enzymes (Newton, 2008). A real evolutionary leap in this field happened with the beginning of the use of DNA identification.

Biological science has proved the genetic exclusiveness of every person (except for identical twins). Thus, another example of the connection of biology with forensic science is associated with 100% accuracy of identification based on DNA analysis. It is enough to compare the suspect’s DNA with the DNA obtained from biological samples found at the crime scene and, obviously, belonging to the offender (Newton, 2008). It remains only to determine whether the samples correspond to each other and make an undoubtedly fair conviction or drop charges against a person from a mismatch of results. Moreover, such a method as the receipt of the fingerprint at the crime scene is one of the most important in forensic science.

Population Evolution and Microbial Life

The role of biology in the study of evolution is extremely significant. For example, with a certain periodicity, the world population is attacked by different viruses and new microorganisms appear constantly. There are four periods of infection in the human organism. The first period is the era of microbial diseases of humanity. Since the beginning of humankind and up to 1800, diseases were caused only by pathogenic microbes (Tibayrenc, 2011). It was connected with the lack of basic hygiene, human life with animals, population density in cities, and the lack of antibiotics. The second period is the era of sharp and dangerous viral infections after 1800 (Tibayrenc, 2011). During this period, large-scale vaccination of the population took place. It should be noted that vaccination is the deliberate infection of the human with an attenuated strain of a microbe or a virus. Nevertheless, despite the significant immune stratum of the population, acute viral diseases, occurring in the form of acute respiratory infections, herpes, and viral colitis became highly widespread. It is another example of the evolution of microbial life. The next stage of the all-out offensive of viral infections is considered between 1960 and 1990 when there was a wide variety of chronic viral infections (Tibayrenc, 2011). During this time period, 80% of the world’s population had strong immunity to many viral infections (Tibayrenc, 2011). Therefore, all viral infections became softer which resulted in the mutation of viruses. Another example of the biology and evolution of microbial life is that multiple mutations of old viruses led to the emergence of new strains that are well adapted to stable immunity of the world’s population to many viral infections. For this reason, the period of acute viral infections has changed with the period of chronic infections.

Biological Diversity Evolution

Biological diversity is a diversity of life on the planet – plants, animals, and ecosystems. This concept also includes the relationship between living beings in ecosystems. Biological diversity is the main outcome and factor of the evolutionary process. The next example is that the emergence of new species and life forms complicates the environment and leads to the progressive development of organisms (Adds, Larkcom, & Miller, 2004). The most complex, evolutionarily advanced forms emerge and thrive in the conditions of the equatorial and tropical zones, where maximum species richness is observed. Another example consists in the fact that a person systematically reduces biodiversity, as a result of the extermination of numerous species and over-exploitation of natural resources. Habitat destruction of biodiversity of the planet steadily declines.

Plant and Animal Evolution

With the help of biology, it can be studied that the first living organisms appeared about 3.5 billion years ago (Adds et al., 2004). The basic conditions of the evolution of plans include several stages. In the Proterozoic era, unicellular aerobic organisms were widespread. The next stage is the formation of soil substrate on the land at the end of the Silurian period. Later, there was the occurrence of multicellular, which enabled the specialization of cells within a single organism. Then, psilophytes appeared on the land. From psilophytes in the Devonian period, a whole group of land plants originated – mosses, clubmosses, horsetails, and ferns reproduced by spores. From seed ferns, gymnosperms occurred. Appeared structures, necessary for seed reproduction, released the sexual process in plants depending on the aquatic environment. Evolution went on the ways to reduce the haploid gametophyte and the predominance of the diploid sporophyte. The Carboniferous period of the Paleozoic era was characterized by a great diversity of terrestrial vegetation. In the Permian period, ancient gymnosperms became the dominant plant group. In the Cretaceous period, the flowering of angiosperms began and it continues until today.

Another example of the evolution concerns animals. The oldest traces of animals belong to the Precambrian. In the Cambrian and Ordovician periods, sponges, coelenterates, worms, echinoderms, trilobites, and mollusks dominated. In the Ordovician, jawless ichthyoids organisms appeared and in the Silurian – fish with jaws. From them, ray-finned fish and crossopterygian originated. From this group of fish, amphibians emerged and, from them, reptiles occurred. The first mammals appeared in the Triassic period of the Mesozoic era (Adds et al., 2004). It should be noted that the conjugate evolution of plants and animals has led to a tremendous diversity of life on earth and changed its appearance.

Population Growth

Throughout the biggest part of human history, population growth was barely noticeable. However, during the XIX century, this process began to process more rapidly. It extremely accelerated in the first half of the XX century. It has led analysts to talk about the population explosion. Among the main causes of such a rapid change in the demographic situation, the success of preventive and curative medicines achieved by this time has attracted the primary attention. It contributed to a significant reduction in the relative indicators of mortality. It is a primary example.

The world population grows by about 90 million people per year (Miller & Spoolman, 2008). The growth of the population causes numerous problems. For instance, it is true for the reduction of animal species. As it was already noted, biodiversity has extremely decreased. Another example is the excessive extraction of natural resources, which, in the future, can lead to disastrous consequences.

Biomes and Ecosystems

Attempts to create a classification of the world’s ecosystems were made a long time ago. Nevertheless, there is still no convenient and universal classification. It is because of the huge diversity of natural types of ecosystems. For example, if a puddle or a bump in the marsh can be a single ecosystem, then, it is obviously impossible to calculate all of the possible bumps or puddles. Therefore, ecologists have decided to focus on larger combinations of ecosystems – biomes. It is a large biological system, which is characterized by a dominant type of vegetation or another feature of the landscape such as biome of deciduous forests of the temperate zone (Adds et al., 2004). Biologists have studied that the geographical distribution of biomes corresponds to soil-climatic zones of the continents.

Conclusion

Modern biology is one of the most important sciences for humans. It is associated with the fact that biology is connected with numerous other sciences. Biological science is a foundation and the basis for the development of many areas of knowledge. Moreover, it studies the process of evolution or certain modern problems, for example, a problem of rapid population growth.