Acne is one of the most common skin diseases in the United States. In fact, nearly 17 million people in the United States suffer from acne. Acne is most typically found in teenagers and young adults, and people from all races are a target. Nearly 85 percent of people between the ages of 12 and 24 get acne at one time or another. For some, acne is not just a ‘every now and then’ problem; it is an on-going problem that can cause scarring and emotional damage. By the time we reach the age of 30, acne usually goes away; however, some people in their forties.. and even fifties… still get acne.
We don’t know the exact cause of how a pimple develops. What we do know is that the pore collapses on itself and blocks oil (sebum) from escaping. This causes the pore to become clogged and infected. The process by which a pimple develops is highly intricate, and we don’t fully understand why one sebaceous gland has a clogging problem while the other does not.
Hormones, diet, evolutionary biology, vitamin deficiency, and stress are factors in the cause of adult acne and teen acne. The real explanation may be a complex mix of many of these factors. Acne is not a serious health threat, but it can cause scars both physically and emotionally.
Sometimes, the hair, sebum, and skin cells clump together into a plug. The bacteria in the plug cause swelling. Then when the plug starts to break down, a pimple grows.
Effective treatments for pimples are out there. Because we know that many factors cause pimples, our time is actually better spent finding and testing effective treatments.
The most common types of pimples are:
1. Whiteheads. Pimples that stay under the skin’s surface.
2. Blackheads. These pimples rise to the surface of the skin and they look black. Contrary to popular belief, the black color is not from dirt.
3. Papules. Tender, small pink bumps that appear on the surface of the skin.
4. Pustules. These pimples are red at the bottom and have pus on top.
5. Nodules. Painful, large, solid pimples that go deep into the skin.
6. Cysts. These deep, painful, pus-filled pimples can cause scars.
Robert Trivers is a living legend in biology and the social sciences, a man the Harvard psychologist Steven Pinker calls ”one of …
By presenting evolutionary biology as an ongoing research effort, this best-seller aims to help readers think like scientists. …
Wide-ranging and inclusive, this text provides an invaluable review of an expansive selection of topics in human evolution, variat…
Encyclopedia of Evolutionary Biology is the definitive go-to reference in the field of evolutionary biology. It provides a fully c…
The third edition of the book once described as ‘simply the best advanced textbook currently available’ has increased its scope wh…
The New York Times best seller by the host of Bill Nye the Science Guy, with a brand new chapter for the paperback edition!”Evolut…
* Evolution The Evolution of Shape HD documentary
Evolution is the change in the inherited characteristics of biological populations over successive generations. Evolutionary processes give rise to diversity at every level of biological organisation, including species, individual organisms and molecules such as DNA and proteins.
All life on Earth is descended from a last universal ancestor that lived approximately 3.8 billion years ago. Repeated speciation and the divergence of life can be inferred from shared sets of biochemical and morphological traits, or by shared DNA sequences. These homologous traits and sequences are more similar among species that share a more recent common ancestor, and can be used to reconstruct evolutionary histories, using both existing species and the fossil record. Existing patterns of biodiversity have been shaped both by speciation and by extinction.
Charles Darwin was the first to formulate a scientific argument for the theory of evolution by means of natural selection. Evolution by natural selection is a process inferred from three facts about populations: 1) more offspring are produced than can possibly survive, 2) traits vary among individuals, leading to different rates of survival and reproduction, and 3) trait differences are heritable. Thus, when members of a population die they are replaced by the progeny of parents better adapted to survive and reproduce in the environment in which natural selection takes place. This process creates and preserves traits that are seemingly fitted for the functional roles they perform. Natural selection is the only known cause of adaptation, but not the only known cause of evolution. Other, nonadaptive causes of evolution include mutation and genetic drift.
In the early 20th century, genetics was integrated with Darwin’s theory of evolution by natural selection through the discipline of population genetics. The importance of natural selection as a cause of evolution was accepted into other branches of biology. Moreover, previously held notions about evolution, such as orthogenesis and “progress” became obsolete. Scientists continue to study various aspects of evolution by forming and testing hypotheses, constructing scientific theories, using observational data, and performing experiments in both the field and the laboratory. Biologists agree that descent with modification is one of the most reliably established facts in science. Discoveries in evolutionary biology have made a significant impact not just within the traditional branches of biology, but also in other academic disciplines (e.g., anthropology and psychology) and on society at large.
Evolution The Evolution of humans documentary 2014