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Song System
A song system, also known as a song control system (SCS), is a series of discrete brain nuclei involved in the production and learning of song in songbirds. It was first observed by Fernando Nottebohm in 1976 in a paper titled "Central control of song in the canary, ''Serinus canarius''", published in the ''Journal of Comparative Neurology''. Operation Based on lesion studies in the zebra finch, the song system can be broken into two general pathways. The direct/descending motor pathway is both necessary and sufficient for normal song production, while the anterior forebrain pathway (AFP)is necessary for song learning but not production. Juvenile birds who have not yet fully learned their songs and that have lesions of the AFP never learn to make normal songs. Adult birds who experience these same lesions continue to sing normally for some time. The song system is sexually dimorphic in many species of songbirds, especially in species in which the male primarily sings. System model ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Songbird
A songbird is a bird belonging to the suborder Passeri of the perching birds (Passeriformes). Another name that is sometimes seen as the scientific or vernacular name is Oscines, from Latin ''oscen'', "songbird". The Passeriformes contains 5000 or so speciesEdwards, Scott V. and John Harshman. 2013. Passeriformes. Perching Birds, Passerine Birds. Version 06 February 2013 (under construction). http://tolweb.org/Passeriformes/15868/2013.02.06 in The Tree of Life Web Project, http://tolweb.org/ ccessed 2017/12/11 found all over the world, in which the vocal organ typically is developed in such a way as to produce a diverse and elaborate bird song. Songbirds form one of the two major lineages of extant perching birds (~4000 species), the other being the Tyranni (~1000 species), which are most diverse in the Neotropics and absent from many parts of the world. The Tyranni have a simpler syrinx musculature, and while their vocalizations are often just as complex and striking as thos ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fernando Nottebohm
Fernando Nottebohm (born 1940 in Buenos Aires) is a neuroscientist and the Dorothea L. Leonhardt Professor at Rockefeller University, as well as being head of the Laboratory of Animal Behavior and director of the Field Research Center for Ecology and Ethology. Education Nottebohm was born in Argentina and received his PhD in zoology from the University of California, Berkeley in 1966 while working with Peter Marler. Afterwards, he conducted extensive investigations of the song of the rufous-collared sparrow (''Zonotrichia capensis''). Research Nottebohm is best known for his work on neurogenesis in the adult vertebrate brain, a phenomenon that previously had been thought impossible by most scientists. Career *1967-71 Assistant professor, Rockefeller University *1971-76 Associate professor, Rockefeller University *1976–present Professor, Rockefeller University *1981–present Director, Rockefeller University Field Research Center for Ecology and Ethology, Millbrook, New Yor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lesion
A lesion is any damage or abnormal change in the tissue of an organism, usually caused by disease or trauma. ''Lesion'' is derived from the Latin "injury". Lesions may occur in plants as well as animals. Types There is no designated classification or naming convention for lesions. Since lesions can occur anywhere in the body and the definition of a lesion is so broad, the varieties of lesions are virtually endless. Generally, lesions may be classified by their patterns, their sizes, their locations, or their causes. They can also be named after the person who discovered them. For example, Ghon lesions, which are found in the lungs of those with tuberculosis, are named after the lesion's discoverer, Anton Ghon. The characteristic skin lesions of a varicella zoster virus infection are called '' chickenpox''. Lesions of the teeth are usually called dental caries. Location Lesions are often classified by their tissue types or locations. For example, a "skin lesion" or a " bra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zebra Finch
The zebra finches are two species of estrildid finch in the genus ''Taeniopygia'' found in Australia and Indonesia. They are seed-eaters that travel in large flocks. The species are: Previously, both species were classified as a single species, the zebra finch (''T. guttata''). However, they were split by the IUCN Red List and BirdLife International in 2016. The International Ornithological Congress followed suit in 2022 based on studies noting differences in plumage, mtDNA divergence, and assortative mating between both species in captivity. The zebra finch was first captured in 1801 during Nicolas Baudin's expedition to Australia. The Indonesian species was described in 1817 by Louis Jean Pierre Vieillot in his ''Nouveau Dictionnaire d'Histoire Naturelle'', where he gave it the scientific name ''Fringilla guttata''. The Australian species was then described in 1837 by John Gould as ''Amadina castanotis''. Its current genus, ''Taeniopygia'', was described in 1862 by Ludwig R ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sexual Dimorphism
Sexual dimorphism is the condition where the sexes of the same animal and/or plant species exhibit different morphological 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. Overview Ornamentation and coloration Common and easily identified types of dimorphism consist of ornamentation and coloration, though not always apparent. A difference in coloration of sexes within a given species is called sexual dichromatism, which is commonly seen in many species of birds and reptiles. Sexual selection leads to the exaggerated dim ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Synaptic Plasticity
In neuroscience, synaptic plasticity is the ability of synapses to strengthen or weaken over time, in response to increases or decreases in their activity. Since memories are postulated to be represented by vastly interconnected neural circuits in the brain, synaptic plasticity is one of the important neurochemical foundations of learning and memory (''see Hebbian theory''). Plastic change often results from the alteration of the number of neurotransmitter receptors located on a synapse. There are several underlying mechanisms that cooperate to achieve synaptic plasticity, including changes in the quantity of neurotransmitters released into a synapse and changes in how effectively cells respond to those neurotransmitters. Synaptic plasticity in both excitatory and inhibitory synapses has been found to be dependent upon postsynaptic calcium release. Historical discoveries In 1973, Terje Lømo and Tim Bliss first described the now widely studied phenomenon of long-term pote ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neural Circuit
A neural circuit is a population of neurons interconnected by synapses to carry out a specific function when activated. Neural circuits interconnect to one another to form large scale brain networks. Biological neural networks have inspired the design of artificial neural networks, but artificial neural networks are usually not strict copies of their biological counterparts. Early study Early treatments of neural networks can be found in Herbert Spencer's ''Principles of Psychology'', 3rd edition (1872), Theodor Meynert's ''Psychiatry'' (1884), William James' ''Principles of Psychology'' (1890), and Sigmund Freud's Project for a Scientific Psychology (composed 1895). The first rule of neuronal learning was described by Hebb in 1949, in the Hebbian theory. Thus, Hebbian pairing of pre-synaptic and post-synaptic activity can substantially alter the dynamic characteristics of the synaptic connection and therefore either facilitate or inhibit signal transmission. In 1959, the neur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neuron
A neuron, neurone, or nerve cell is an electrically excitable cell that communicates with other cells via specialized connections called synapses. The neuron is the main component of nervous tissue in all animals except sponges and placozoa. Non-animals like plants and fungi do not have nerve cells. Neurons are typically classified into three types based on their function. Sensory neurons respond to stimuli such as touch, sound, or light that affect the cells of the sensory organs, and they send signals to the spinal cord or brain. Motor neurons receive signals from the brain and spinal cord to control everything from muscle contractions to glandular output. Interneurons connect neurons to other neurons within the same region of the brain or spinal cord. When multiple neurons are connected together, they form what is called a neural circuit. A typical neuron consists of a cell body (soma), dendrites, and a single axon. The soma is a compact structure, and the axon and dend ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Testosterone
Testosterone is the primary sex hormone and anabolic steroid in males. In humans, testosterone plays a key role in the development of Male reproductive system, male reproductive tissues such as testes and prostate, as well as promoting secondary sexual characteristics such as increased muscle and bone mass, and the growth of androgenic hair, body hair. In addition, testosterone in both sexes is involved in health and well-being, including moods, behaviour, and in the prevention of osteoporosis. Insufficient levels of testosterone in men may lead to abnormalities including frailty and bone loss. Testosterone is a steroid from the androstane class containing a ketone and a hydroxyl group at positions three and seventeen respectively. It is Biosynthesis, biosynthesized in several steps from cholesterol and is converted in the liver to inactive metabolites. It exerts its action through binding to and activation of the androgen receptor. In humans and most other vertebrates, testost ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bird Vocalization
Bird vocalization includes both bird calls and bird songs. In non-technical use, bird songs are the bird sounds that are melodious to the human ear. In ornithology and birding, songs (relatively complex vocalizations) are distinguished by function from calls (relatively simple vocalizations). Definition The distinction between songs and calls is based upon complexity, length, and context. Songs are longer and more complex and are associated with territory and courtship and mating, while calls tend to serve such functions as alarms or keeping members of a flock in contact. Other authorities such as Howell and Webb (1995) make the distinction based on function, so that short vocalizations, such as those of pigeons, and even non-vocal sounds, such as the drumming of woodpeckers and the "winnowing" of snipes' wings in display flight, are considered songs. Still others require song to have syllabic diversity and temporal regularity akin to the repetitive and transformative patte ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
