Systemic lupus erythematosus, often abbreviated as SLE or lupus, is a systemic autoimmune disease (or autoimmune connective tissue disease) in which the bodyâs immune system mistakenly attacks healthy tissue.ystemic lupus erythematosus, often abbreviated as SLE or lupus, is a systemic autoimmune disease (or autoimmune connective tissue disease) in which the bodyâs immune system mistakenly attacks healthy tissue.
Natural selection will only cause evolution if there is enough genetic variation in a population. Before the discovery of Mendelian genetics, one common hypothesis was blending inheritance. But with blending inheritance, genetic variance would be rapidly lost, making evolution by natural selection implausible.
Biological evolution is genetic change in a population from one generation to another. The speed and direction of change is variable with different species lines and at different times. Continuous evolution over many generations can result in the development of new varieties and species.Likewise, failure to evolve in response to environmental changes can, and often does, lead to extinction. When scientists speak of evolution as a theory they do not mean that it is a mere speculation.It is a theory in the same sense as the propositions that the earth is round rather than flat or that our bodies are made of atoms are theories.iological evolution is genetic change in a population from one generation to another. The speed and direction of change is variable with different species lines and at different times. Continuous evolution over many generations can result in the development of new varieties and species.