- This article deals primarily with Acquired characteristics by humans. You can improve this article by adding information about Acquired characteristics by plants and non-human animals.
An acquired characteristic is a non-heritable change in a function or structure of a living biotic material caused after birth by disease, injury, accident, deliberate modification, repeated use, disuse, or misuse, or other environmental influences. Acquired traits, which is synonymous with acquired characteristics, are not passed on to offspring through reproduction alone.
The changes that constitute acquired characteristics can have many manifestations and degrees of visibility but they all have one thing in common: they change a facet of a living organisms' function or structure after the organism has left the womb.
- The children of former bodybuilder Arnold Schwarzenegger may have highly developed or otherwise above average musculature.
- "Lucky", an adult, three-legged dog who got her name after surviving being hit by a car when she was a pup, just gave birth to five puppies. None had limps, malformed/abnormal legs, or were missing a leg.
- Bonsai are normal plants that have been grown to remain small through cultivation techniques.
Acquired characteristics can be minor and temporary like bruises, blisters, shaving body hair, and body building. Permanent but inconspicuous or invisible ones are corrective eye surgery and organ transplant or removal. Semi-permanent but inconspicuous or invisible traits are vaccinations and laser hair removal. Perms, tattoos, scars, and amputations are semi-permanent and highly visible.
Applying makeup and nailpolish, dying one's hair or applying henna to the skin, and tooth whitening are not examples of acquired traits. They change the appearance of a facet of an organism, but do not change the structure or functionality.
Inheritance of acquired characters was historically proposed by renowned theorists such as Hippocrates, Aristotle, and French naturalist Jean-Baptiste Lamarck. Conversely, this hypothesis was denounced by other renowned theorists such as Charles Darwin. Today, although Lamarckism is generally discredited, there is still debate on whether some acquired characteristics in organisms are actually inheritable.
- 1 Disputes
- 2 Types
- 3 Origin
- 4 See also
- 5 References
- 6 External links
Acquired characteristics, by definition, are characteristics that are gained by an organism after birth as a result of external influences or its own activities that change its structure or function and cannot be inherited. Therefore, every condition an organism is born with must be considered an inherited characteristic.
Inherited characteristics, by definition, are characteristics that are gained or predisposed to by an organism as a result of genetic transmission from its parents and will be passed to the organism's offspring. Therefore, every condition an organism does not gain or develop because of inheritance of its parents' genetic information must be considered an acquired characteristic.
Certain genetic conditions
It is fairly common for mammalian eyes to change color in the first years of life. This happens, with human infants and kittens being some well-known examples, because the eyes of the baby, just like the rest of its body, are still developing. This change can be as simple as blue to brown, or can involve multiple color changes in which neither the child's parents nor his/her doctors know when the changes will stop and what the final eye color will be.
Changes in eye color signal changes in the arrangement and concentration of pigment in the iris, which is an example of structural color. Even though this change happens after birth, it is strictly as result of genes. While changes in eye appearance (and function, and structure) that occur because of acquired characteristics like injury, illness, old age, or malnutrition are definitely acquired characteristics, the infantile color change as described above is usually considered inherited.
When diseases are caused by environmental influences, such as iodine deficiency or lead poisoning, their resultant symptoms are unequivocally agreed to be acquired characteristics. However, it is debatable whether changes in bodily functions due to disorders that are partly or wholly genetic in origin are actually "acquired".
Wholly genetic disorders, such as Huntingtons, are ticking time-bombs that are inherited from parents' genes and are present before birth but the symptoms that develop, aka are "acquired", after birth are simply delayed manifestations of the inherited trait.
Disorders that are partially genetic, such as ALS and allergies, mean the organism has inherited a predisposition to develop, aka "acquire", a certain condition but that inherited increased likelihood can be reduced or further increased depending on acquired characteristics of the organism.
New mutations, (often somatic, spontaneous and sporadic), not inherited from either parent are called de novo mutations. The consensus on whether certain prenatal spontaneous mutations and genetic disorders that occur as a result of meiotic and chromosome errors or during cell division after conception, like Cystic fibrosis and Down syndrome, are considered to be acquired or inherited is unclear. Mutations and meiotic errors can be considered inherited since the organism is born with them in its genes, but they can also be seen as prenatal acquired characteristics since they are not actually inherited from its parents. With de novo mutations and division errors, the relationship between the offspring's altered genes and gene inheritance from the parents is technically spurious. These genetic errors can affect the mind as well as the body and can result in schizophrenia, autism, bi-polar disorder , and cognitive disabilities.
The definitions of inherited and acquired characteristics leave a gray area for trauma, pre-existing and gestational maternal conditions that affect the fetus, as well as chemical and pathogen exposures and trauma that happen before and while an organism is born, such as AIDS, syphilis, Hepatitis B, chickenpox, rubella, unregulated gestational diabetes, and fetal alcohol syndrome. Most infections won't affect a fetus if the pregnant mother contracts it, but some can be transmitted to babies via the placenta or during birth, and others cause more severe symptoms in pregnant women or can cause complications to the pregnancy.
The World Health Organization defines health as a state of complete physical, mental and social well-being, and not merely the absence of disease or infirmity. Acquired characteristics don't need to affect the health of an organism, (a scar, suntan, or perm) but examples that do are often the first that come to mind when thinking of acquired characteristics since they are the easiest to observe and the ones that we, ourselves, are most familiar with.
Physical acquired characteristics can stem from various environmental influences such as disease, modification, injury, and regular or infrequent use of body parts.
Mental traits are acquired by learning and adapting native traits to the environment of the individual.
Sentiments are the result of the compounding of primary emotions, being "bound up with knowledge and ideas." Only through vast experience in the natural world can humans learn to recognize objects in all of the various orientations in which we encounter them on a day-to-day basis. The ability to do something well is an acquired characteristic, since a skill comes from one's knowledge, practice, aptitude, etc.
Many acquired characteristics, such as injuries and diseases, directly affect only the mind but indirectly affect the body or directly affect only the body but indirectly affect the mind.
Suppose you develop an articulation disorder after being hit in the head with a fastball from a Pro baseball pitcher. Once your concussion wears off, this is your only symptom. There's nothing wrong with your body, and nothing wrong with most of your mind but you stutter and slur and mispronounce your words so that people have a very hard time understanding you.
How would such a condition affect your life if you were a child? A child would be teased mercilessly by peers and have trouble communicating with friends and family.
A student would not be able to communicate easily with classmates (collaborative assignments), teachers, tutors, and certain classes (choir, public speaking).
What if you had a job where you needed to be able to talk to people? You wouldn't be able to easily talk to customers, other employees, or your boss. You couldn't answer phones or make calls, greet customers, do presentations. You couldn't call your pet's name. You wouldn't even be able to use a fast food drive-through or tell your waitress what you wanted to order! You couldn't say, "I love you," to your child, parent, or significant other.
The example in the above link deals with the loss of a single mental function. Imagine what would happen if a part of your body stopped working. Even something as simple as a broken finger causes many changes in lifestyle to compensate for the difference in function: writing, typing, drawing, driving, hobbies like gardening, fishing, or sports, using video game and TV controls, texting and dialing phone numbers, using cutlery to eat, opening a bag of chips or soda can, preparing food for yourself or your family, playing with your child or pet, unlocking and opening doors, bathing, brushing your teeth and hair, dressing yourself, typing your shoes, and more.
The person unable to pronounce words clearly would suffer additional stress, anxiety, frustration, and emotional upset from his functional limitation. There would be anxiety over financial hardships like bills from medical exams and tests, and a possible leave of absence or termination from work. Physical effects of your articulation disorder could be paper cuts from your notepad, headaches over the stress, stubbed toes and sprained ankles from rushing to where you accidentally left you notepad, pulling a muscle from hauling a laptop around, etc. Worry could induce ulcers. If you have to cut back on spending, your (and your family's) nutrition could suffer. There would be less money for fine dining, going out with friends, and indulging in toys and hobbies.
Those close to you - family, friends, lovers - would be negatively affected by your limitation and your relationship with them would suffer as well.
There are four main types of disease: pathogenic disease, deficiency disease, hereditary disease, and physiological disease.
Congenital disorders, known more commonly as birth defects, are DEFINITION.
Suppose a pregnant woman is shot in her abdomen and the bullet hits the fetus, causing a non-fatal injury. Depending on the length of time between injury and birth, the baby could be born either with a still-healing wound or with a fully healed scar. Regardless of its state of healing, the gunshot wound could be considered an inherited characteristic, since the baby is born with the condition, or could be considered an acquired characteristic, since the condition did not happen as a result of genes inherited from its parents.
The gray area is that a prenatal gunshot wound obviously isn't an inherited, genetic condition but it can't be an acquired trait because it didn't happen after the baby's birth.
Hormones are chemicals released by a cell or a gland in one part of the body that affect cells in other parts of the organism.
Chemicals are substances with distinct molecular compositions that are produced by or used in a chemical process.
Drugs are any substance that, when absorbed into the body of a living organism, alter normal bodily function. Drugs can be legal and be used as is medically prescribed by a doctor or be illegal to buy, sell, possess, and administer. They can be naturally occurring (such as caffeine and cannabis) or man-made (such as Chlorpromazine). Both legal and illegal drugs can be misused and abused. They have varying levels of dependence and some can cause addiction.
Main article: Barratry (common law)
- Common commercial: "Women who took drug X during their pregnancy and had babies born with these conditions may be entitled to financial compensation."
Maternal conditions during gestation
Main article: Fraternal birth order and male sexual orientation
- A correlation between fraternal birth order and male sexual orientation has been suggested to be responsible for up to 15 percent of homosexuality. It is hypothesized to have something to do with changes induced in the mother's body when gestating a boy that affects subsequent sons, possibly an in-utero maternal immune response.
Maternal environment and exposures
There is also reason to believe that the immune system of a baby will be healthier if, during pregnancy, the mother's immune system was regularly stimulated by exposure to pathogens.
"...A mother's farm exposure affects her baby's T regulatory cells. These cells, it is now believed, act to suppress immune responses and thereby maintain immune system homeostasis to contribute to healthy immune development. ... The babies of mothers exposed to farms have more and better functioning regulatory T cells."—
It is posited that the absence of exposure to parasites, bacteria, and viruses is playing a significant role in the development of autoimmune diseases in the more sanitized Western industrialized nations. Lack of exposure to naturally occurring pathogens may result in an increased incidence of autoimmune diseases. (See hygiene hypothesis.)
A complete explanation of how environmental factors play a role in autoimmune diseases has still not been proposed. However epidemiological studies, such as the meta analysis by Leonardi-Bee, et al., have helped to establish the link between parasitic infestation and autoimmune disease development, in other words, exposure to parasites reduces incidence of an autoimmune disease developing.
"Immunological diseases, such as eczema and asthma, are on the increase in westernized society and represent a major challenge for 21st century medicine. ...[G]rowing up on a farm directly affects the regulation of the immune system and causes a reduction in the immunological responses to food proteins," which not only means less severe reactions to food allergies, lactose intolerance, gluten sensitivity, etc., but reductions in the likelihood of developing them in the first place.
Disease is a broad term that refers to any condition that impairs the normal physical or mental (or both) function of an organism. (Though this definition includes injuries, it will not be discussed here). Diseases can arise from infection, environmental conditions, accidents, and inherited diseases.
It is not always easy to classify the source of a health problem. For instance, people can develop gout, which is known to cause permanent or near permanent changes to the human body, because of diet, inherited genetic predisposition, as a secondary condition from other diseases, or as an unintended side effect of certain medications.
For infectious, environmental, and genetically predisposed conditions, lifestyle choices such as exercise, nutrition, stress level, hygiene, home and work environments, use or abuse of legal and illegal drugs, and access to healthcare (including an individual's financial ability and personal willingness to seek medical attention) especially in the early stages of an illness all combine to determine a person's risk factors for developing a disease or condition.
The World Food Program and UNICEF reported last year that chronic malnutrition had left 42 percent of North Korean children stunted — meaning their growth was seriously impaired, most likely permanently. An earlier report by the U.N. agencies warned that there was strong evidence that physical stunting could be accompanied by intellectual impairment.—Demick, Barbara. 2-14-2004. The Seattle Times.
This statistic, or versions of it, have been quoted for some time. In 2010, the late Christopher Hitchens put the difference at six inches in an article in Slate, titled "A Nation of Racist Dwarfs". Martin Bloem is head of nutrition at the World Food Programme, which has been providing food aid to North Korea since 1995. He says poor diet in the early years of life leads to stunted growth. "Food and what happens in the first two years of life is actually critical for people's height later," he says.Today, according to the World Food Programme, "one in every three children [in North Korea] remains chronically malnourished or 'stunted', meaning they are too short for their age".—Knight, Richard. 4-22-2012. BBC News
cougar with shortened legs at Big Cat Rescue
Poor nutrition and frequent injury and disease can reduce the individual's adult stature, but the best environment cannot cause growth to a greater stature than is determined by heredity.
Vitamin K deficiency malnutrition Nutrition disorder
Accidental injuries, most of which can be predicted and thus prevented, are the unintentional negative outcomes of unforeseen or unplanned events or circumstances which may have been avoided or prevented if reasonable measures had been taken or if the risks involving the circumstances leading up to the accident been recognized and acted upon (minimized).
Battery is a criminal offense involving the use of force against another that results in harmful or offensive contact. (Assault is fear/belief of impending battery.) Violence is defined by the WHO as the intentional use of physical force or power, threatened or actual, against oneself or others that either results in or has a high likelihood of resulting in injury, death, psychological harm, maldevelopment or deprivation. Consent
Head trauma in the form of a traumatic brain injury, stroke, drug or alcohol abuse, and infection have been known in some cases to cause changes to a person's mental processes, the most common being amnesia, ability to deal with stress and changes in aggression. There have also been documented cases of a person's personality changing more drastically, the best-known case being Phineas Gage, who in 1848 who survived a 1.1 meter long tamping iron being driven through his skull (though almost all presentations of Gage's subsequent personality changes are grossly exaggerated).
There is also the rare condition called Foreign Accent Syndrome in which someone who has suffered a brain injury will appear to speak in a new language or dialect. This is typically thought to be due to an injury to the linguistic center of the brain causing speech impairment that just happens to sound like a persons non-native language. This is thought to be the reasoning behind the urban legend where someone wakes from a coma or surgery and suddenly speaks a new language.
Body modification is the deliberate altering of the human body for any non-medical reason, such as aesthetics, sexual enhancement, a rite of passage, religious reasons, to display group membership or affiliation, to create body art, shock value, or self-expression.
The frequency of occurrence depends on the location, extent, and number of modifications, and, perhaps most importantly, on the mind of each individual being asked to accept the modifications on another.
The change can be extreme but still be accepted or at least tolerated by the majority (cosmetic surgery), or be extreme and opposed by most people (neck rings). Ear piercing is a minor aesthetic alteration that is widely accepted (on females' ears). The acceptance of highly diverse tattoos and body piercings depends on location, size, and number and, perhaps most importantly, on the mind of each individual being asked to accept it.
Also known as maiming, mutilation is any form of physical injury aimed at degrading the bodily appearance or function of a living organism's body. Examples, include amputation, foot binding, and genital cutting. The reasons for these changes can be rite of passage,
Like other acquired characteristics, body modification results in permanent physiological changes that cannot be passed on to offspring genetically alone.
Use and disuse of body parts
Constant physical exercise such as swimming, running, and weight lifting can cause muscles to develop. However, muscles and other body parts can also waste away through atrophy due to disuse of said body parts. Both of these phenomena occur most of the time due to the living style of the organism and their effects on the physiology of the organism constitute of acquired characteristics such as either stronger muscles or disintegrated tissue.
Many repetitive activities (sports, manual labor, chewing) create wear patterns and leave impressions on the bones and fascia that are highly specialized (sometimes even unique) to the activity. Over a lifetime, even such simple activities as posture and gait leave telltale impressions on our bodies. shoes.
Complications of pregnancy Wilson's disease
- Lamarck's inheritance of acquired characteristics
- Jean-Baptiste Lamarck
- August Weismann's Experiments on the inheritance of acquired characteristics
- Nature versus nurture
- Behavioural genetics
- Environmental disease
- Environmental factor
- Hygiene hypothesis
- Dangerous goods
- Hazardous waste
- Toxic waste
- A Civil Action
- Recreational drug use
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- What is body modification?