Behavioural genetics is the field of study that examines the role of genetics in animal (including human ) behaviour . Often associated with the " nature versus nurture " debate, behavioural genetics is highly interdisciplinary , involving contributions from biology , genetics , epigenetics , ethology , psychology , and statistics . Behavioural geneticists study the inheritance of behavioural traits. In humans, this information is often gathered through the use of the twin study or adoption study . In animal studies, breeding, transgenesis , and gene knockout techniques are common. Psychiatric genetics is a closely related field.
Mendelian inheritance was initially derived from the work of Gregor Johann Mendel published in 1865 and 1866 which was re-discovered in 1900. It was initially very controversial. When Mendel's theories were integrated with the Chromosome Theory of Inheritance by Thomas Hunt Morgan in 1915, they became the core of classical genetics . [ edit ] History The laws of inheritance were derived by Gregor Mendel , a nineteenth-century Austrian monk conducting hybridization experiments in garden peas ( Pisum sativum ). [ 1 ] Between 1856 and 1863, he cultivated and tested some 29,000 pea plants.
Eugenics is the applied science of the bio- social movement which advocates practices to improve the genetic composition of a population , usually a human population. [ 2 ] [ 3 ] It is a social philosophy advocating the improvement of human hereditary traits through the promotion of higher reproduction of more desired people and traits, and reduced reproduction of less desired people and traits. [ 4 ]
Arginine vasopressin ( AVP ), also known as vasopressin , argipressin or antidiuretic hormone ( ADH ), is a neurohypophysial hormone found in most mammals . Its two primary functions are to retain water in the body and to constrict blood vessels. Vasopressin regulates the body's retention of water by acting to increase water absorption in the collecting ducts of the kidney nephron. [ 1 ] Vasopressin increases water permeability of the kidney's collecting duct and distal convoluted tubule by inducing translocation of aquaporin-CD water channels in the kidney nephron collecting duct plasma membrane. [ 2 ] Vasopressin is a peptide hormone that controls the reabsorption of molecules in the tubules of the kidneys by affecting the tissue's permeability.
The ventral tegmentum ( tegmentum is Latin for covering ), better known as the ventral tegmental area (VTA), is a group of neurons located close to the midline on the floor of the midbrain ( mesencephalon ). The VTA is the origin of the dopaminergic cell bodies of the mesocorticolimbic dopamine system and is widely implicated in the drug and natural reward circuitry of the brain. It is important in cognition , motivation , drug addiction , intense emotions relating to love, and several psychiatric disorders . The VTA contains neurons that project to numerous areas of the brain, from the prefrontal cortex (PFC) to the caudal brainstem and several regions in between.
Line segments in the golden ratio A golden rectangle with longer side a and shorter side b , when placed adjacent to a square with sides of length a , will produce a similar golden rectangle with longer side a + b and shorter side a .
Forkhead box protein P2 also known as FOXP2 is a protein that in humans is encoded by the FOXP2 gene , [ 1 ] located on human chromosome 7 (7q31, at the SPCH1 locus). [ 2 ] [ 3 ] FOXP2 orthologs [ 4 ] have also been identified in all mammals for which complete genome data are available. The FOXP2 protein contains a forkhead-box DNA-binding domain , making it a member of the FOX group of transcription factors , involved in regulation of gene expression . In addition to this characteristic forkhead-box domain, the protein contains a polyglutamine tract , a zinc finger and a leucine zipper .
The bootstrap paradox is a paradox of time travel in which information or objects can exist without having been created. After information or an object is sent back in time, it is recovered in the present and becomes the very object/information that was initially brought back in time in the first place. Numerous science fiction stories are based on this paradox, which has also been the subject of serious physics articles. [ 1 ]
The Cretaceous–Paleogene (K–Pg) boundary (formerly known as the K–T boundary ) is a geological signature , usually a thin band , dated to 66.0 Ma (million years) ago. [ 1 ] K is the traditional abbreviation for the Cretaceous period , and Pg is the abbreviation for the Paleogene period. The boundary marks the end of the Cretaceous period, which is the last period of the Mesozoic era , and marks the beginning of the Paleogene period of the Cenozoic era. The boundary is associated with the Cretaceous–Paleogene extinction event , a mass extinction , which is considered to be the demise of the non- avian dinosaurs. [ 2 ] The boundary layer was once known as the K–T boundary, but Tertiary has been deprecated as a formal time or rock unit by the International Commission on Stratigraphy . [ 3 ]
Science and religion began to go their separate ways in the Renaissance. The process continued when Galileo and Descartes started to ponder on the nature of the universe. To do so, they had to stray into the territory traditionally the exclusive domain of the church and, in Europe in the first half of the 17th century, the church was powerful indeed. Those who offended it too loudly or too fundamentally could burn in a hell that was very much on earth. So it was out of an instinct of self-preservation that Galileo divided the world into two. He said that there are primary qualities that are external and objective, such as temperature, wavelength, hardness and so on, and secondary qualities that are subjective, such as the sensations of heat, colour and pain.
In physical cosmology , galaxy filaments , also called supercluster complexes or great walls (sometimes called "hyperclusters" [ 1 ] [ 2 ] or "great attractors" [ 3 ] [ 4 ] ), are amongst the largest known cosmic structures in the universe . They are massive, thread-like structures with a typical length of 50 to 80 megaparsecs h -1 that form the boundaries between large voids in the universe. [ 5 ] Filaments consist of gravitationally bound galaxies ; parts where a large number of galaxies are very close to each other (in cosmic terms) are called superclusters . Discoveries of structures larger than superclusters started in the 1980s. In 1987 astronomer R.
The ultimate fate of the universe is a topic in physical cosmology . Many possible fates are predicted by rival scientific theories, including futures of both finite and infinite duration. Once the notion that the universe started with a rapid inflation nicknamed the Big Bang became accepted by the majority of scientists, [ 1 ] the ultimate fate of the universe became a valid cosmological question, one depending upon the physical properties of the mass/energy in the universe, its average density, and the rate of expansion. There's a growing consensus among cosmologists that the universe will continue to expand forever. [ 2 ]
The multiverse (or meta-universe ) is the hypothetical set of multiple possible universes (including the historical universe we consistently experience) that together comprise everything that exists and can exist: the entirety of space , time , matter , and energy as well as the physical laws and constants that describe them. The term was coined in 1895 by the American philosopher and psychologist William James . [ 1 ] The various universes within the multiverse are sometimes called parallel universes .
Brane cosmology refers to several theories in particle physics and cosmology motivated by, but not exclusively derived from, superstring theory and M-theory . [ edit ] Brane and bulk The central idea is that the visible, four-dimensional universe is restricted to a brane inside a higher-dimensional space, called the "bulk". If the additional dimensions are compact , then the observed universe contains the extra dimensions, and then no reference to the bulk is appropriate.
Artist's Representation Of P-Branes floating in Hyperspace In theoretical physics , a membrane , brane , or p -brane is a spatially extended mathematical concept that appears in string theory and related theories (e.g. M-theory and brane cosmology ). The membrane exists in a static number of dimensions.