Many scientists have discussed many theories of evolution. It was a scientific competition between scientists to proof the accuracy of their theories and hypothesis. As a result of these theories, understanding of the principles that are related to microevolution, natural selection, adaptation within the species, gene flow and genetic drift, isolation, and hybridization, will help to evaluate all of these theories. At national and global levels, countries take serious actions and legislations to secure species survival. During the studying of the simple green plants (bryophytes), scientists discovered that they are beneficial to human survival. They also have ecological importance. Another important topic is the diversity of the seed plants and the importance of them to both environment and human. It is also important to understand the diversity of bacteria and viruses and to study their structure and functions. They also are essential to both human and environment.
Theories of Evolution
The theories of evolution can be divided into two periods, before and after Darwin. Before Darwin, I would like to discuss the most the two famous theories about evolution. The first method is invented by Jean Baptiste Lamarck (1744 – 1829) (Prothero and Buell, 2007). He proposed a theory of evolution called, “The Law of Use and Disuse.” He stated that if the animal uses an organ frequently, the organ will develop and strengthen, while if it is not used, it will atrophy. He also invented a theory of “The Inheritance of Acquired Characteristics”. He believed that if organ characteristics developed through adapting to a new lifestyle, it would transfer it to its offspring. For example, the giraffe used its neck to reach the tree leave, so its neck stretched and this characteristic has transferred to next generations. I completely disagree with this theory because of the way inheritance works. The second theory of evolution is stated by Charles Lyell, 1830, (Anthro.palomar.edu, 2015). He explained the biological evolution by the geological process called Uniformitarianism. He assumed that the processes that are happening now had operated in the past. As a geologist, I can ensure that the impact of uniformitarianism influences the biological evolution of the same species. The second period is after Charles Darwin, 1859 theory of evolution (Darwin, Einstein, and Smith, 1859). He explained the development of life from nonlife. He argued that the most complicated creatures are evolved from more simple ancestors naturally over time. I agree with this theory as it is more reasonable to me. A good example that makes me agreed with this theory the evidence of the evolution of horse toes. The ancestors of horse were five-toes, fox-sized. By the time and natural selection, horse toes became equine. I would like to maintain that the Darwinian Theory is the most acceptable theory to me. Lamarck theory failed to illustrate why the offspring of metalworkers does not have developed muscles as their fathers. The Lyell theory can be acceptable, but it cannot give a clear interpretation on how creatures are evolved.
One of the theories that Darwin proposed in called Natural Selection. It is a process of preserving functional advantages of a species to survive in the wild. It can be used to control some species populations by selective breeding. It has four processes; variation, inheritance, high rate of population growth and, differential survival and reproduction. Microevolution is a change in gene frequency within a group (Evolution.berkeley.edu, 2015). We can observe the evolution over short periods of time, for example, an increase of the pesticide resistance gene in crop pests. Adaptation within a species is a change in species characteristics, size, color, or organs of offspring due to environmental changes. Adaptation is the change in the frequency of a gene. Adaptation can be by evolving of a gene as a result of natural selection for a particular function. An excellent example of this perspective is the streamline body shape of marine fish. Gene flow and genetic drift are a crucial part of evolution theories. Gene flow is a movement of a gene from population to population. Migration is one of the ways that the gene may flow amongst populations. Genetic drift is when unpredictable changes happened in allele frequencies. In a small population, genetic drift is more impactful to the gene pool than in bigger communities. It is a one of several strategies that evolution can occur in the population. The last aspect that can affect the development is isolation and hybridization. There are several ways of isolation; geographic isolation, the reproductive isolation that is divided into pre-zygotic and post-zygotic isolation. Hybridization is the interbreeding of different species to produce different offspring.
Secure species survival
Nationally in the UK, there is Wildlife and Countryside Act, 1981. It is a very efficient legislation as it covers the protection of wildlife, including wild plants and wild animals. The great achievement of this act is the establishment of protected areas as the UK has 5,000 SSSIs (Sites of Special Scientific Interests) that cover around 8% of the land area of England and 12% of Wales (GHK Consulting Ltd, 2015). Another strategy that is very successful in the UK is Special Areas of Conservation (SACs). It helps to conserve 189 habitat types and 788 species that are identified in Annexes I, and II of the EC Habitats Directive; however, the UK has about 652 SACs (Jncc.defra.gov.uk, 2015). In my opinion, the UK is doing very well to preserve species. Internationally there are several effective strategies. One of these strategies is The Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES). The effectiveness of this approach is that CITES protect 35,000 species against over-exploitation (cites.org, 2015). Despite this strategy achieved a high achievement in protecting species, it failed to protect wildlife in some areas, such as areas of war. It also cannot enforce non-developed countries to fight illegal trades. In Egypt, for example, the government cannot prevent illicit trade in endangered species of fish and coral reefs. Another useful strategy, I believe, is IUCN, the International Union for Conservation of Nature, Red list. It is succeeded to preserve 23,250 species till 2015. It is also achieved to protect Iberian lynx (Lynx pardinus) as its population has increased from 52 mature in 2002 to 156 in 2016 (iucn.org, 2015).
Jncc.defra.gov.uk, (2016). Special Areas of Conservation (SAC). [online] Available at: http://jncc.defra.gov.uk/page-23 [Accessed 7 Dec. 2015].
They are non-vascular land plants that are a small, herbaceous plant. Bryophyte plants are different than vascular plants. Its sporophytes have a very short life, and they are attached to their gametophytes as dependents to obtain nutrients from them. Bryophyte sporophytes consist of an unbranched stalk, or seta, and a single terminal sporangium, and they are 2-5 cm tall (Schofield, 2014). Bryophyte gametophore structure contains stems, roots, and leaves while the sporophyte produces spores. Sporophytes are unknown in some bryophytes, and the gametophyte reproduces asexually. Bryophyte classes are Division Bryophyta, or Mosses (Class Bryopsida, or Musci), Division Marchantiophyta or Liverworts (class Heptapsida, or Hepaticae), and Division Anthocerotophyta or Hornworts (Class Anthocerotopsida, or Anthocerotae) (Mauseth, 1998).
Mauseth, J. (1998). Botany. Boston: Jones and Bartlett Publishers.
Bryophytes are considered a simple green plant that is ecologically relevant and for human as well. The most important mosses that are vital to human survival are peat mosses. They are a primary source of fuel and they consider a vast reservoir of different energy. It is used, till now, for cooking in some countries. About 95% of peat harvested in Ireland is burned to produce electricity (Science.jrank.org, 2015). A human can use peats to improve the soil water-holding capacity. I believe that peat mosses play an imperative role in human survival. You can imagine that our lives without Bryophytes, I would argue that we would have an issue in energy demands. The most important role they play is they are sensitive indicators of pollutants in the atmosphere.
As we have seen, that green plants are essential for human survival. It also has ecological importance. Mosses, the liverworts, and lichens are the vast vegetation sources in the absence of other vegetation. They occupy the areas of hills to prepare the soil for angiospermic and other plant growth. Sphagnum plants have a great ecological importance as they cover the whole surface of water help in minimizing the rate of evaporation. They also give an appearance of the soil from the surface. I also would maintain that some bryophytes play a critical role in protecting soil erosion. Despite bryophytes plans are useful for the environment; it might not be useful for other plants such as a vascular plant. I think bryophyte mat can kill vascular seeds if it was deep enough.
Adaptation, Survival, and classification of seeds
Terrestrial plants are well-adapted to grow and persist. Seeds provide a significant adaptation for terrestrial plants. A diploid embryo that exists in the seed is developed into a sporophyte. It also stores tissue to help continuous growth, and it acts as a protective coat. Several layers of hard tissue cover seeds to prevent desiccation of it. Seeds are scattering widely by wind, animals, or water. It helps them to avoid food competitions with their parents. Plants can access the deep water by their vascular systems. The most important adaptation strategy, I guess, this plant can reduce water loss across the cell wall as it has a waxy cuticle. The other important strategy is that plant has stomata on its leaves that can close and open. Plants can be tolerant dry conditions as they develop spores with a protective wall. I believe that plant has very efficient adaptation strategies.
Seed survival is crucial to both environment and human survival. Seeds are the source of food to human while other seeds are valuable raw materials for the manufacture of industrial chemicals. They are not only necessary for human vegetation, but it also plays a crucial role in human welfare. Human can eat seeds directly, or they might exist in fruit that human eat. I usually use an apple in the morning as a diet for me. It helps me to lose weight and builds my body. Seeds are used to manufacture flour, starch, oil, and alcohol. Environmentally, seeds are used to restore ecosystems by the plantation. This is one of the most important usages of seeds environmentally. Seed banks and seed genetic engineering can help in restoring the forests. I argue that seeds can control plant population and crop variety. Despite seed genetic engineering is required to conserve plants, it might, in my opinion, be an evil for plant diversity. Any unwell-studied genetic modification or an error in the gene of a seed, it can damage a whole species of the plant. Seeds can act like a nuclear bomb for other plant species if it is misused or genetically damaged.
In order to identify seed species, there are two ways to classify seeds. Classification of seeds is by internal morphology, and by families. By internal morphology, seeds are divided into two classes; Monocotyledonous and Dicotyledonous. The bulk of monocotyledonous families’ seeds (Gramineae, and Cyperaceae) have reserve food tissue. Its embryo has endosperm and seed leaves. Dicotyledonous embryo occupies a small space of the seed cavity. The classification of seed by families depends on the seed structure. This strategy is varied from a system to another. There are four systems of classification, and they are divided into two main groups (Plantexplorers.com, 2015). Gymnospermae includes conifers, cycads, and Welwitschia. Angiospermae is called “Magnoliophyta”, and it is divided into six main groups; Amborellaceae, Nymphaeaceae, Illiciacea, Magnoliids, monocotyledons, and Eudicots.
The reproduction strategy of these two groups differs from group to another. The reproduction in gymnosperms takes place inside cones due to the absence of flowers or ovaries. The seed can be transferred by the wind, over water, carried by the animal or by explosions. In angiosperms, seeds are developed inside the ovary.
Bacteria and Viruses Species, Structure, and Function
Bacteria are divided into many classes. Class Cyanobacteria species can obtain their energy by conducting photosynthesis. It is blue bacteria, and they existed as blue-green algae. I consider this species as they caused the great Oxidation Event. They produce oxygen as a byproduct of photosynthesis. Class Prochlorobacteriae is one of the bacteria species that are discovered recently as photosynthetic bacteria. It contains chlorophyll A & B. Class Eubacteria is unicellular and contains DNA, and its cell has a wall. This is the most important species as it is used for medical applications. Class Archaebacteria includes bacteria that live in harsh conditions. They are anaerobic bacteria. Viruses have two species; Viroid, and Prions. Viroid contains small single-stranded RNA. They can infect plants that they are responsible for crop damage. Prions are smaller than viruses, and it contains neither DNA nor RNA.
Bacteria size is ranged between 0.2 µm and 700µm. They have several shapes. It differs from species to another (Fastbleep.com, 2015):
- Rod-shaped or bacillus: E.coli and Bacillus cereus.
- Spherical (coccus): Staphylococcus epiderminis.
- Curved (Vibrio, spirochetes): Vibrio cholera.
- Square-shaped (Arcola)
- Star-shaped (Stella), and
- Flagella: has a leg-like structure that helps to hold the bacterium.
The function of the cell structure is vital to protect the bacteria. Call wall is responsible prevent the osmosis shock of the cell and cell wall damage. Cytoplasmic membrane controls the traffic of substance in and out of the cell. Chromosome holds the bacteria gene. Plasmid carries the genetic information of the bacteria. Ribosome participates in protein synthesis. Flagella helps cell to move. The minerals are stored in Inclusion body while Pili is responsible for attaching the cell to the host. Endospore is tough and helps bacteria to survive in hard conditions.
Fastbleep.com, (2015). Bacterial Cell Structure and Function – Microbiology | Fastbleep. [online] Available at: http://www.fastbleep.com/biology-notes/35/112/654 [Accessed 31 Dec. 2015].
Viruses have a different structure than bacteria. A protein coat called, “a capsid” surrounding the nucleic acid core. Viruses have two shaped, viral shape, icosahedron – 20 triangular faces, for example, chicken pox, and helix-coiled spring, for example, Rabies. Bacteriophage T4 Structure has many components. Head consists of genetic material surrounded by capsid; it is responsible for protecting the genome. Neck connects the head to the tail and consists of many discs. The tail is a contractile protein that helps in the injection of genetic material into the host cell. The base plate is responsible for attachment to the host (YouTube, 2015).
Horne, R. (1974). Virus structure. New York: Academic Press.
The Importance of Bacteria and Viruses
Both bacteria and viruses are important ecologically and for a human. Ecologically, viruses are essential in freshwater and saltwater regulation. They play a vital role in the carbon cycle in the marine environment as they destroy the bacteria. Viruses and bacteria form more than 90% of the biomass in the marine environment (Viral Roles in Ecosystems, 2015). I agree with the fact that viruses destruct harmful algae bloom that they kill other marine organisms. This is a very useful role of viruses in marine life. However, viruses are not always harmless. Viruses can kill some of the marine animals, for example, Parvovirus was a responsible of melting if sea stars along the West Coast of Canada and the US (Lee, 2014). Bacterial, as well as viruses, play a vital role in the environment. They are responsible for decomposition of dead bodies. I would maintain that this is one of the most important roles of bacteria. The absence of those bacteria can make our lives full of diseases because of rotten dead bodies. Another active role of the bacteria is that they are useful in nitrogen fixation and make it available to plants, for example, Rhizobium and Cyanobacteria. Some scientist can argue that some bacteria are harmful to the environment; however, I find that the benefits of bacteria to the environment are more effective than their adverse effects.
Viruses and bacteria are not only relevant to the environment. They are also necessary for a human. Most of the bacteria help human to digest food and produce vitamins such as gut bacteria. The real thing in the bacteria is that the human can use them to produce dairy food such as, cheese, yogurt, and also sourdough bread. I like the uses of bacteria and viruses to make the vaccine. The human takes the advantages of the science to fight the harmful effect of bacteria and viruses by themselves. Despite I believe that viruses have the significant adverse impact on human health, viruses can help human as they can kill harmful bacteria. My strong belief is that the adverse effects of the viruses are more than its useful effect.
As we have seen that I agreed with the Darwin theory of evolution as I find it more accurate and logic. It can be considered in the definition of microevolution and natural selection theories. The UK and other international agency have maintained very efficient practices to preserve species. The study of bryophytes and simple green plants lead the scientist to discover the importance of these plants to human survival, and also, it has ecological important as well. Seeds adapt to the terrestrial life by maintaining several useful strategies. The one of the methods to understand the diversity of seed is to know how they classified and how they reproduce. This led me to study viruses and bacteria diversity as they are crucial to maintaining our environment and our survival. I can tell that bacteria have the more beneficial effect to human than viruses. However, the modern science takes full advantages of turning viruses to be useful than it though before.
- Anthro.palomar.edu, (2015). Early Theories of Evolution:Â Pre-Darwinian Theories. [online] Available at: http://anthro.palomar.edu/evolve/evolve_1.htm [Accessed 26 Dec. 2015].
- Biotechnologyforums.com, (2016). Role of Bacteria in Environment. [online] Available at: http://www.biotechnologyforums.com/thread-44.html [Accessed 3 Jan. 2016].
- Butchart, S., Stattersfield, A., Bennun, L., Shutes, S., AkÃ§akaya, H., Baillie, J., Stuart, S., Hilton-Taylor, C. and Mace, G. (2004). Measuring Global Trends in the Status of Biodiversity: Red List Indices for Birds. PLoS Biology, 2(12), p.e383.
- Cites.org, (2015). The CITES species | CITES. [online] Available at: https://www.cites.org/eng/disc/species.php [Accessed 26 Dec. 2015].
- Darwin, C., Einstein, A. and Smith, A. (1859). On The Origin Of Species & Other Bonus Works. 1st ed. [ebook] London: Amazon Digital Services, Inc. Available at: http://www.amazon.com/Origin-Species-Other-Bonus-Works-ebook/dp/B018MYKF2I [Accessed 20 Dec. 2015].
- Elvidge, S. (2016). Facts About Bacteria and Viruses. [online] Scienceprojectideas.co.uk. Available at: http://www.scienceprojectideas.co.uk/facts-about-bacteria-viruses.html [Accessed 30 Dec. 2015].
- Evolution.berkeley.edu, (2015). What is microevolution?. [online] Available at: http://evolution.berkeley.edu/evolibrary/article/evoscales_02 [Accessed 26 Dec. 2015].
- Fastbleep.com, (2015). Bacterial Cell Structure and Function – Microbiology | Fastbleep. [online] Available at: http://www.fastbleep.com/biology-notes/35/112/654 [Accessed 31 Dec. 2015].
- Fws.gov, (2015). How CITES Works. [online] Available at: http://www.fws.gov/international/cites/how-cites-works.html [Accessed 26 Dec. 2015].
- GHK Consulting Ltd, (2015). Benefits of Sites of Special Scientific Interest. [pdf] Available at: http://users.aber.ac.uk/mec/Publications/Reports/Benefits%20of%20SSSIs%20final%20revised%20report%20june%202011.pdf [Accessed 26 Dec. 2015].
- Horne, R. (1974). Virus structure. New York: Academic Press.
- Iucn.org, (2015). IUCN – Conservation successes overshadowed by more species declines â€“ IUCN Red List update. [online] Available at: http://www.iucn.org/news_homepage/?21561/Conservation-successes-overshadowed-by-more-species-declines–IUCN-Red-List-update [Accessed 26 Dec. 2015].
- Jncc.defra.gov.uk, (2016). Special Areas of Conservation (SAC). [online] Available at: http://jncc.defra.gov.uk/page-23 [Accessed 7 Dec. 2015].
- Kurstak, E. and Maramorosch, K. (1978). Viruses and environment. New York: Academic Press.
- L. Gittleman, J. (2014). adaptation | biology and physiology. [online] Encyclopedia Britannica. Available at: http://www.britannica.com/science/adaptation-biology-and-physiology [Accessed 26 Dec. 2015].
- Lee, J. (2014). Why Are Millions of Starfish ‘Melting’?. [online] News.nationalgeographic.com. Available at: http://news.nationalgeographic.com/news/2014/11/141117-starfish-dying-epidemic-virus-animal-ocean-science/ [Accessed 2 Jan. 2016].
- Mauseth, J. (1998). Botany. Boston: Jones and Bartlett Publishers.
- Natural England, (2010). Sites of Special Scientific Interest. Protecting Englandâ€™s natural treasures. [online] Natural England. Available at: http://publications.naturalengland.org.uk/file/94022 [Accessed 26 Dec. 2015].
- Plantexplorers.com, (2015). Plant Classification – PlantExplorers.comâ„¢. [online] Available at: https://www.plantexplorers.com/explorers/biographies/linnaeus/classification.htm [Accessed 31 Dec. 2015].
- Prions and Viroids. (2015). Boundless. [online] Available at: https://www.boundless.com/biology/textbooks/boundless-biology-textbook/viruses-21/prions-and-viroids-139/prions-and-viroids-558-11769/ [Accessed 31 Dec. 2015].
- Prothero, D. and Buell, C. (2007). What the fossils say and why it matters. New York: Columbia University Press.
- Schofield, W. (2014). bryophyte | plant. [online] Encyclopedia Britannica. Available at: http://www.britannica.com/plant/bryophyte [Accessed 27 Dec. 2015].
- Science.jrank.org, (2015). Bryophyte – Importance Of Mosses. [online] Available at: http://science.jrank.org/pages/1051/Bryophyte-Importance-mosses.html [Accessed 27 Dec. 2015].
- Viral Roles in Ecosystems. (2015). Boundless. [online] Available at: https://www.boundless.com/microbiology/textbooks/boundless-microbiology-textbook/viruses-9/viral-ecology-129/viral-roles-in-ecosystems-664-5414/ [Accessed 27 Dec. 2015].
- YouTube, (2015). T4 phage structure. Available at: https://www.youtube.com/watch?v=uyjBZIfqK7c [Accessed 31 Dec. 2015].
- YouTube, (2015). Virology 2015 Lecture #4: Structure of viruses. Available at: https://www.youtube.com/watch?v=MRkcZ6gXiTY&index=4&list=PLGhmZX2NKiNlsqbNuq__7jeedNkdEaZBv [Accessed 31 Dec. 2015].