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These are timelines of brain development events in different animal species.
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A brain is an organ that serves as the center of the nervous system in all vertebrate and most invertebrate animals. It is located in the head, usually close to the sensory organs for senses such as vision. It is the most complex organ in a vertebrate's body. In a human, the cerebral cortex contains approximately 14–16 billion neurons, and the estimated number of neurons in the cerebellum is 55–70 billion. Each neuron is connected by synapses to several thousand other neurons. These neurons typically communicate with one another by means of long fibers called axons, which carry trains of signal pulses called action potentials to distant parts of the brain or body targeting specific recipient cells.
Homininae, also called "African hominids" or "African apes", is a subfamily of Hominidae. It includes two tribes, with their extant as well as extinct species: 1) the tribe Hominini ―and 2) the tribe Gorillini (gorillas). Alternatively, the genus Pan is sometimes considered to belong to its own third tribe, Panini. Homininae comprises all hominids that arose after orangutans split from the line of great apes. The Homininae cladogram has three main branches, which lead to gorillas, and to humans and chimpanzees via the tribe Hominini and subtribes Hominina and Panina. There are two living species of Panina and two living species of gorillas, but only one extant human species. Traces of extinct Homo species, including Homo floresiensis have been found with dates as recent as 40,000 years ago. Organisms in this subfamily are described as hominine or hominines.
Sexual dimorphism is the condition where the sexes of the same species exhibit different characteristics, particularly characteristics not directly involved in reproduction. The condition occurs in most animals and some plants. Differences may include secondary sex characteristics, size, weight, colour, markings, or behavioural or cognitive traits. These differences may be subtle or exaggerated and may be subjected to sexual selection and natural selection. The opposite of dimorphism is monomorphism, which is when both biological sexes are phenotypically indistinguishable from each other.
Sexual differentiation is the process of development of the sex differences between males and females from an undifferentiated zygote. Sex determination is often distinct from sex differentiation, sex determination is the designation for the development stage towards either male or female while sex differentiation is the pathway towards the development of the phenotype.
Tomorrow Woman is a fictional character, an android in stories published DC Comics. She debuted in JLA #5, and was created by Grant Morrison and Howard Porter. Within the DC Comics canon, she is created by the mad scientist super-villains Professor Ivo and T.O. Morrow. Given human-like physical characteristics and false memories of a human life, Tomorrow Woman believes herself to be a new superhero born with psionic abilities due to a "four-lobed brain". Her true purpose is to infiltrate and then kill the Justice League. In her first appearance, she says she exclusively has telekinetic abilities, but a later flashback issue of JLA: Tomorrow Woman (1998) reveals that she also has telepathic abilities.
Encephalization quotient (EQ), encephalization level (EL), or just encephalization is a relative brain size measure that is defined as the ratio between observed to predicted brain mass for an animal of a given size, based on nonlinear regression on a range of reference species. It has been used as a proxy for intelligence and thus as a possible way of comparing the intelligences of different species. For this purpose it is a more refined measurement than the raw brain-to-body mass ratio, as it takes into account allometric effects. Expressed as a formula, the relationship has been developed for mammals and may not yield relevant results when applied outside this group.
Evolutionary neuroscience is the scientific study of the evolution of nervous systems. Evolutionary neuroscientists investigate the evolution and natural history of nervous system structure, functions and emergent properties. The field draws on concepts and findings from both neuroscience and evolutionary biology. Historically, most empirical work has been in the area of comparative neuroanatomy, and modern studies often make use of phylogenetic comparative methods. Selective breeding and experimental evolution approaches are also being used more frequently.
The evolution of human intelligence is closely tied to the evolution of the human brain and to the origin of language. The timeline of human evolution spans approximately seven million years, from the separation of the genus Pan until the emergence of behavioral modernity by 50,000 years ago. The first three million years of this timeline concern Sahelanthropus, the following two million concern Australopithecus and the final two million span the history of the genus Homo in the Paleolithic era.
Bissektipelta is a genus of ankylosaurine thyreophoran dinosaurs that lived in Asia during the Late Cretaceous in what is now the Bissekty Formation of Uzbekistan. Bissektipelta is a monospecific genus, containing only the type species B. archibaldi.
The Cosmic Calendar is a method to visualize the chronology of the universe, scaling its currently understood age of 13.8 billion years to a single year in order to help intuit it for pedagogical purposes in science education or popular science.
Dates in days
The house mouse has a gestation period of 19 to 21 days. Key events in mouse brain development occur both before and after birth, beginning with peak neurogenesis of the cranial motor nuclei 9 days after conception, up to eye opening which occurs after birth and about 30 days after conception.
The principles that govern the evolution of brain structure are not well understood. Brain to body size scales allometrically. Small bodied mammals have relatively large brains compared to their bodies whereas large mammals have smaller brain to body ratios. If brain weight is plotted against body weight for primates, the regression line of the sample points can indicate the brain power of a primate species. Lemurs for example fall below this line which means that for a primate of equivalent size, we would expect a larger brain size. Humans lie well above the line indicating that humans are more encephalized than lemurs. In fact, humans are more encephalized than all other primates.
A nidicolous animal is an animal that stays at its birthplace for a long time because it depends on the parents for food, protection, and the learning of survival skills. They are the opposite of nidifugous species, which leave their parents more quickly and survive independently.
The evolution of nervous systems dates back to the first development of nervous systems in animals. Neurons developed as specialized electrical signaling cells in multicellular animals, adapting the mechanism of action potentials present in motile single-celled and colonial eukaryotes. Many primitive systems, like those found in complex protozoa, use non-electrical signaling for motility and other aspects necessary for survival. Data suggests that these systems, which use a chemical gradient for messaging, evolved into the electrical-signaling cells known today.
The following outline is provided as an overview of and topical guide to evolution:
Neurogenesis is the process by which nervous system cells, the neurons, are produced by neural stem cells (NSCs). It occurs in all species of animals except the porifera (sponges) and placozoans. Types of NSCs include neuroepithelial cells (NECs), radial glial cells (RGCs), basal progenitors (BPs), intermediate neuronal precursors (INPs), subventricular zone astrocytes, and subgranular zone radial astrocytes, among others.
Timurlengia is an extinct genus of tyrannosauroid theropod dinosaur found in Uzbekistan, in the Bissekty Formation in the Kyzylkum Desert, hailing from the Turonian age of the early Late Cretaceous. The type species is Timurlengia euotica.
This article presents a detailed timeline of events in the history of computing from 2020 to the present. For narratives explaining the overall developments, see the history of computing.