The Medical Academy named after S. I. Georgievsky of Vernadsky CFU

CFU
COURSE STUDENT
VIVEK GOSWAMI
SCIENTIFIC LEADER
SVETLANA BRIGHT

mechanisms of adaptation. Adaptation is biological and social.

to our environment.An adaptationis any variation that can increase one’s

biological fitness in a specific environment; more simply it is the successful interaction of a population with its environment.Adaptations may be biological or cultural in nature. Biological adaptations vary in their length of time, anywhere from a few seconds for a reflex to a lifetime for developmental acclimatization or genetics. The biological changes that occur within an individual’s lifetime are also referred to as functional adaptations.

severity and duration of stressors in the environment.A stressor is

anything that disrupts homeostasis, which is a “condition of balance, or stability, within a biological system…”(Jurmain et al 2013: 322). Stressors can be abiotic, e.g., climate or high altitude, biotic, e.g., disease, or social, e.g., war and psychological stress. Cultural adaptations can occur at any time and may be as simple as putting on a coat when it is cold or as complicated as engineering, building, and installing a heating system in a building.

is constant and lasts for many generations (O’Neil 1998-2013). The

presence of the sickle cell allele in some human populations is one example. Keep in mind that genetic adaptations are environmentally specific.In other words, while a particular gene may be advantageous to have in one environment (AKA a genetic adaptation), it may be detrimental to have in another environment. z Ac

to occur and is reversible within an individual’s lifetime no

matter if it occurs when one is a child or an adult. ▪ Short-termacclimatizationcan occur within seconds of exposure to a stressor.This type of response quickly reverses when the stressor is no longer present. Imagine stepping out of an air-conditioned building or car into a 90 degree day. Your body will quickly begin to perspire in an attempt to cool your body temperature and return to homeostasis. When the temperature declines, so will your perspiration. Tanning is another shortterm response, in this case to increased UV-radiation exposure especially during summer months, which can occur within hours. Tans are generally lost during the winter when UV-radiation decreases.

development. It’s also called ontological acclimatization or developmental adjustment. Note

that these cannot take place once the individual is fully grown. There is usually a “magic time window” of when the acclimatization can occur. This adaptation can take months to years to acquire. ▪ A famous example of this is those who have grown up at high altitude vs. those who have moved to high altitude as adults. Those who were born at high altitude tend to develop larger lung capacities than do those who were not born at high altitude, but moved there later in life. However, developmental adjustment occurs in response to cultural stressors as well. Intentional body deformation has been documented throughout human history. The ancient Maya elite used cradle boards to reshape the skull. Foot binding in China, now an illegal practice, was considered an mark of beauty and enabled girls to find a wealthy spouse.

size and shape
▪ Race

or function of an organism or any of its parts

that results from natural selection and by which the organism becomes better fitted to survive and multiply in its environment. ▪ a form or structure modified to fit a changed environment. ▪ the ability of a species to survive in a particular ecological niche, especially because of alterations of form or behavior brought about through natural selection.

populations does not affect fitness one way or another. ...

If this difference does not affect their survival and reproduction one way or the other, then the variants are not adaptations; they are simply neutral variation that is maintained by mutation and genetic drift

a new imperative in the face of global climate change

and the oldest problem in human history. Humans have evolved a wide range of adaptation strategies in response to localised environmental changes, which have contributed strongly to both biological and cultural diversity. The evolving set of locally driven, ‘bottom-up’responses to environmental change is collectively termed ‘autonomous adaptation,’while its ob

responses to biodiversity change caused by an aggressive ‘invasive’ plant,

Lantana camara L., in several agri-forest communities of southern India. The results show that a variety of adaptation processes are developing to make Lantana less disruptive and more useable—from avoidance through mobility strategies to utilizing the plant for economic diversification. However, there is currently no clear synergy or policy support to connect them to a successful long-term adaptation pathway. These results are evaluated in relation to broader trends in adaptation analysis and governance to suggest ways of improving our understanding and support for human adaptation to biodiversity change at the household, community, and regional livelisystem levels, especially in societies highly dependent on local biodiversity for their livelihoods

growth and development. It's also called ontological acclimatization or developmental

adjustment. ... There is usually a “magic time window” of when the acclimatization can occur. This adaptation can take months to years to acquire

was connected in some way with adaptation of organisms to

changing environmental conditions. In developing the theory of evolution by natural selection, Wallace and Darwin both went beyond simple adaptation by explaining how organisms adapt and evolve. The idea of natural selection is that traits that can be passed down allow organisms to adapt to the environment better than other organisms of the same species. This enables better survival and reproduction compared with other members of the species, leading to evolution. • Wallace believed that the evolution of organisms was connected in some way with adaptation of organisms to changing environmental conditions. In developing the theory of evolution by natural selection, Wallace and Darwin both went beyond simple adaptation by explaining how organisms adapt and evolve. The idea of natural selection is that traits that can be passed down allow organisms to adapt to the environment better than other organisms of the same species. This enables better survival and reproduction compared with other members of the species, leading to evolution.

behavioral adaptation is how emperor penguins in Antarctica crowd together

to share their warmth in the middle of winter. • Scientists who studied adaptation prior to the development of evolutionary theory included Georges Louis Leclerc Comte de Buffon. He was a French mathematician who believed that organisms changed over time by adapting to the environments of their geographical locations. Another French thinker, Jean Baptiste Lamarck, proposed that animals could adapt, pass on their adaptations to their offspring, and therefore evolve. The example he gave stated the ancestors of giraffes might have adapted to a shortage of food from short trees by stretching their necks to reach higher branches. In Lamarck’s thinking, the offspring of a giraffe that stretched its neck would then inherit a slightly longer neck. Lamarck theorized that behaviors aquired in a giraffe's lifetime would affect its offspring. However, it was Darwin’s concept of natural selection, wherein favorable traits like a long neck in giraffes suvived not because of aquired skills, but because only giraffes that had long enough necks to feed themselves survived long enough to reproduce. Natural selection, then, provides a more compelling mechanism for adaptation and evolution than Lamarck's theories.

example of biological adaptation can be seen in the bodies

of people living at high altitudes, such as Tibet. Tibetans thrive at altitudes where oxygen levels are up to 40 percent lower than at sea level. Breathing air that thin would cause most people to get sick, but Tibetans’ bodies have evolved changes in their body chemistry. Most people can survive at high altitudes for a short time because their bodies raise their levels of hemoglobin, a protein that transports oxygen in the blood. However, continuously high levels of hemoglobin are dangerous, so increased hemoglobin levels are not a good solution to high-altitude survival in the long term. Tibetans seemed to have evolved genetic mutations that allow them to use oxygen far more efficently without the need for extra hemoglobin.

can be defined as “is adapted a living being.” This

short cut that was inspired by Laborite (1976) introduced the idea that, if a being lives and reproduces, it is because it has adjusted its biological functions to its external conditions. Morin adheres to this general idea by affirming that adaptation is the prime and general condition of all existence (Morin, 1985). In greater detail, biological adaptation designates above all a process that can be transposed at an individual level, resulting from genetic organization at a cellular level. Thus, the immune system is capable of perception and acquisition on a physiological level. This process is then qualified as “acclimatization” or “apprenticeship” (Prochiantz, 1997; Stewart, 1994). Adaptation is biological and

each essential, elementary functions are insured by distinct biological modules

which are exquisitely adapted to their particular role (see for instance Csete et Doyle, 2002). This modular organisation is robust and at the same time flexible: when a new trait emerges, natural selection does not start from scratch, but from the available modules: existing organs, tissues and cells, existing genes and gene networks. By combining modules—the LEGO bricks— within an organism it is possible to make something new. A common theme that has emerged from analyses in evolutionary biology is thus that organisms are robust and flexible systems. If the surroundings of an organism change, its developmental systems provide the ability to adapt to achieve and maintain some function (Breuker, 2006). Robustness and flexibility are thus two antinomic properties that result from modularity. This “property of the systems that are susceptible to deforming themselves in a coherent and autonomous manner in order to respond to internal and external stress,” (Lambert and Rezsöhazy, 2004, p.304) is called plasticity and is seen as the real “adaptive capacity” of life.

the result of a long term evolution produced by natural

selection. The spatial scale can reach that of a population, an ecosystem or even Earth, as maintained by the Gaia hypothesis in its definition of the Earth as “a dynamic, physiological system that includes the biosphere and maintains our planet in harmony with life” (Lovelock, 1969, p.30). However, biological adaptation also describes the product (state, character) of the evolving processes. Gould and Vrba, in particular, see a character as an adaptation if it fulfils a role for an individual in the present whereas Bock (1980) defines a character as an adaptation if it contributes to the reproductive success of the individual. These subtleties guide Reeve and Sherman (1993) to emphasize the importance of defining adaptation in an appropriate way in relation to the problem addressed. The interactions between the organisms and their environment and the mechanisms of adaptation are now better understood.