For natural selection to occur, several premises must be satisfied. Firstly, there must be variation in a population. If all individuals are the same, there is no variation on which selection can occur. Secondly, these traits must be heritable, meaning they are passed from parent to offspring. Natural selection cannot operate on traits that have no genetic basis. There must also be differential reproduction, which means that some individuals must reproduce more than others. When all of these factors occur, natural selection results in evolution as advantageous traits propagate throughout the population.
Natural selection is quite variable, as changes in the environment impact what traits are advantageous in a particular time and place. A good of example of this comes from Galapagos finches. These birds have varying beak sizes. Wide beaks are best for eating hard seeds, while long narrow beaks are more adept at exploiting the fleshy fruit from trees. Typically narrow beaks are more prevalent, but during drought conditions when trees cannot produce fruit, seeds become a more abundant food item. This results in those finches with wide beaks having more food available and reproducing more than those with narrow beaks. When droughts persist over many years, wide beaks replace narrow beaks as the most common, but this trend reverses when droughts end and fruits once again become available.
Ecological succession is the gradual process by which ecosystems change and develop over time. Nothing remains the same and habitats are constantly changing.
<h3><u>There are two main types of succession, primary and secondary</u><u>:</u><u>-</u></h3>
Primary succession is the series of community changes which occur on an entirely new habitat which has never been colonized before. For example, a newly quarried rock face or sand dunes.
Secondary succession is the series of community changes which take place on a previously colonized, but disturbed or damaged habitat. For example, after felling trees in a woodland, land clearance or a fire.
The Major Points:
The species living in a particular place gradually change over time as does the physical and chemical environment within that area.
Succession takes place because through the processes of living, growing and reproducing, organisms interact with and affect the environment within an area, gradually changing it.
Each species is adapted to thrive and compete best against other species under a very specific set of environmental conditions. If these conditions change, then the existing species will be outcompeted by a different set of species which are better adapted to the new conditions.
The most often quoted examples of succession deal with plant succession. It is worth remembering that as plant communities change, so will the associated micro-organism, fungus and animal species. Succession involves the whole community, not just the plants.
<h2>ꜰᴏʟʟᴏᴡ ᴍᴇ❤</h2>
Vitamin C is required to produce the collagen present in the extracellular matrix.
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Vitamin C</h2>
Vitamin C, or ascorbic acid, is a vitamin that dissolves in water and can be found in citrus and vegetables. Vitamin C is key to preventing and treating scurvy, which is a disease that occurs from Vitamin C deficiency (most of the time due to malnutrition or severe alcoholism); the first symptoms of scurvy are weakness and fatigue, but if it does not get treated properly, it can progress to anemia, hemorrhage, periodontitis, changes in personality, and finally death.
Vitamin C is a necessary element for tissue healing, collagen synthesis, and neurotransmitter enzymatic production. It is vital for immune system function and is necessary for the functioning of numerous enzymes. It has antioxidant properties as well.
Learn more about Vitamin C here: brainly.com/question/1165711
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