MARINE SPECIES BELONGING TO KINGDOM MONERA

The Earth is 4.6 billion years old and microbial life is thought to have first appeared between 3.8 and 3.9 billion years ago; in fact, 80% of Earth's history was exclusively microbial life. Microbial life is still the dominant life form on Earth. It has been estimated that the total number of microbial cells on Earth on the order of 25 billions of cells, making it the major fraction of biomass on the planet. The kingdom Monera which includes all the bacteria like the diatoms and some algae are in a way the lowest among the living world. All bacteria, majority of the organisms belonging to this kingdom are microscopic that they cannot be seen or observed by naked eyes. These organisms falling in the kingdom monera have existed since creation though their richness has been disturbed by various causes attributed by both natural and artificial.

Bacteria are found everywhere. They are the simplest forms of life consisting of cells that lack nuclei and chromosomes (which house the genetic material in other organisms) and have a single layer to the cell wall. Bacteria reproduce by splitting in two. They do this very rapidly and can produce 4 000 million of offspring in just 24 hours. Some can make their own food using the sun’s energy, but most live by decaying plants and animals, or as parasites of living things. ‘Germ’ is a common name for bacteria. They are some of the oldest forms of life, and fossils exist of bacteria that lived 3.5 billion years ago when temperatures were high and there was no oxygen on the earth. Some bacteria can respire anaerobically by breaking down sulphur compounds; others use hydrogen to reduce carbon dioxide. Salt-loving forms regulate the global salinity.

The following below are forms of bacteria marine species that have existed since creation.

Halophilic bacteria live in salty conditions for instance where hot sun concentrates sea water. Cyanobacteria being one of these bacteria, these were earlier called the blue green algae. A very successful group on primitive earth. They could carry out photosynthesis and the oxygen releases during the process changed the earth’s atmosphere and gradually the level of oxygen increased in the earth’s atmosphere.

Cyanobacteria and mycoplasmas are the best examples of bacteria. As they don't have ether containing linkages like Archaea, they are grouped into a different category and hence a different domain. There is a great deal of diversity in this domain, such that it is next to impossible to determine how many species of bacteria exist on the planet.

Archaea these were ancient bacteria that evolved under ferociously hot conditions. Archaea are prokaryotic cells which are typically characterized by membranes that are branched hydrocarbon chains attached to glycerol by ether linkages. The presence of this ether containing linkages in Archaea adds to their ability of withstanding extreme temperature and highly acidic conditions. Extreme halophiles that organisms which thrive in highly salty environment and hyperthermophiles the organisms which thrive in extremely hot environment are best examples of Archaea. They are methane producing bacteria, salt-loving bacteria and sulphur bacteria. Sub-kingdom Eubacteria More recent very diverse group of bacteria.

In the oceans and seas, light and nutrients are important controlling factors for productivity. "Oceans," light penetrates only into the uppermost level of the oceans, so photosynthesis occurs in surface and near-surface waters. Marine primary productivity is high near coastlines and other areas where upwelling brings nutrients to the surface, promoting plankton blooms. Runoff from land is also a source of nutrients in estuaries and along the continental shelves. Among aquatic ecosystems, algal beds and coral reefs have the highest net primary production.

Natural Causes of Extinction

Climatic Heating and Cooling; Climate Change is caused by a number of things. The effect that climate has on extinction is very big. The biodiverse Earth can't keep up with the rapid changes in temperature and climate. The species are not used to severe weather conditions and long seasons, or a changing chemical make-up of their surroundings. As more species die, it is only making it more difficult for the survivors to find food. The warmer climates we are used to present-day are perfect for diseases and epidemics to thrive.

Changes in sea levels and currents; the changes in sea levels and currents are a result, in part, of the melting freshwater. The denser, saltier water sinks and forms the currents that marine life depends on. Ocean floor spreading and rising also affects sea level. A small rise in the ocean floor can displace a lot of water onto land that is all ready occupied. The gases from the volcanic activity can also be absorbed by the water, thus changing the chemical composition, making it unsuitable for some life.