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African Forest Elephant
The African forest elephant (''Loxodonta cyclotis'') is one of the two living species of African elephant, along with the African bush elephant. It is native to humid tropical forests in West Africa and the Congo Basin. It is the smallest of the three living elephant species, reaching a shoulder height of . As with other African elephants, both sexes have straight, down-pointing tusks, which begin to grow once the animals reach 1–3 years old. The forest elephant lives in highly sociable family groups of up to 20 individuals. Since they forage primarily on leaves, seeds, fruit, and tree bark, they have often been referred to as the 'megagardener of the forest'; the species is one of many that contributes significantly to maintaining the composition, diversity and structure of the Guinean Forests of West Africa and the Congolese rainforests. Seeds of various plants will go through the elephant's digestive tract and eventually pass through in the animal's droppings (likely in a new ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pleistocene
The Pleistocene ( ; referred to colloquially as the ''ice age, Ice Age'') is the geological epoch (geology), epoch that lasted from to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was finally confirmed in 2009 by the International Union of Geological Sciences, the cutoff of the Pleistocene and the preceding Pliocene was regarded as being 1.806 million years Before Present (BP). Publications from earlier years may use either definition of the period. The end of the Pleistocene corresponds with the end of the last glacial period and also with the end of the Paleolithic age used in archaeology. The name is a combination of Ancient Greek () 'most' and (; Latinized as ) 'new'. The aridification and cooling trends of the preceding Neogene were continued in the Pleistocene. The climate was strongly variable depending on the glacial cycle, oscillating between cold Glacial period, glacial periods and warmer Interglacial, int ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cameroon
Cameroon, officially the Republic of Cameroon, is a country in Central Africa. It shares boundaries with Nigeria to the west and north, Chad to the northeast, the Central African Republic to the east, and Equatorial Guinea, Gabon, and the Republic of the Congo to the south. Its coastline lies on the Bight of Biafra, part of the Gulf of Guinea, and the Atlantic Ocean. Due to its strategic position at the crossroads between West Africa and Central Africa, it has been categorized as being in both camps. Cameroon's population of nearly 31 million people speak 250 native languages, in addition to the national tongues of English and French, or both. Early inhabitants of the territory included the Sao civilisation around Lake Chad and the Baka people (Cameroon and Gabon), Baka hunter-gatherers in the southeastern rainforest. Portuguese discoveries, Portuguese explorers reached the coast in the 15th century and named the area ''Rio dos Camarões'' (''Shrimp River''), which became ''C ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Elephas
''Elephas'' is a genus of elephants and one of two surviving genera in the Family (biology), family Elephantidae, comprising one extant species, the Asian elephant (''E. maximus''). Several extinct species have been identified as belonging to the genus, extending back to the Pliocene or possibly the late Miocene. Description Species of ''Elephas'' have distinct bossing of the parieto-occipital region of the skull. The premaxillae bones containing the tusks are tapered. Evolutionary history Relationships of living and extinct elephantids based on DNA, after Palkopoulou et al. 2018.Asian elephants share a closer common ancestry with mammoths (genus ''Mammuthus'') than they do with African elephants (''Loxodonta''). The oldest species attributed to the genus ''Elephas'' is ''E. nawataensis'' from the Late Miocene-Early Pliocene of Kenya, though the validity of this species and its relationship to ''Elephas'' has been doubted. The oldest species widely attributed to the genus ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Palaeoloxodon
''Palaeoloxodon'' is an extinct genus of elephant. The genus originated in Africa during the Early Pleistocene, and expanded into Eurasia at the beginning of the Middle Pleistocene. The genus contains the largest known species of elephants, with mature bulls over tall at the shoulders and over in weight, representing among the largest land mammals ever, including the African '' Palaeoloxodon recki'', the European straight-tusked elephant (''Palaeoloxodon antiquus'') and the South Asian '' Palaeoloxodon namadicus. P. namadicus'' has been suggested to be the largest known land mammal by some authors based on extrapolation from fragmentary remains, though these estimates are highly speculative. In contrast, the genus also contains many species of dwarf elephants that evolved via insular dwarfism on islands in the Mediterranean, some like '' Palaeoloxodon falconeri'' less than in shoulder height as fully grown adults, making them the smallest elephants known. The genus has a long ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Straight-tusked Elephant
The straight-tusked elephant (''Palaeoloxodon antiquus'') is an extinct species of elephant that inhabited Europe and Western Asia during the Middle Pleistocene, Middle and Late Pleistocene. One of the largest known elephant species, mature fully grown bulls on average had a shoulder height of and a weight of . Straight-tusked elephants likely lived very similarly to modern elephants, with herds of adult females and juveniles and solitary adult males. The species was primarily associated with temperate and Mediterranean woodland and forest habitats, flourishing during interglacial periods, when its range would extend across Europe as far north as Great Britain and Denmark and eastwards into Russia, while persisting in southern Europe during glacial periods, when northern Europe was occupied by Steppe mammoth, steppe mammoths and later Woolly mammoth, woolly mammoths. Skeletons found in association with stone tools and in one case, a wooden spear, suggest they were scavenged and h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gene Flow
In population genetics, gene flow (also known as migration and allele flow) is the transfer of genetic variation, genetic material from one population to another. If the rate of gene flow is high enough, then two populations will have equivalent allele frequencies and therefore can be considered a single effective population. It has been shown that it takes only "one migrant per generation" to prevent populations from diverging due to Genetic drift, drift. Populations can diverge due to Natural selection, selection even when they are exchanging alleles, if the selection pressure is strong enough. Gene flow is an important mechanism for transferring genetic diversity among populations. Migrants change the distribution of genetic diversity among populations, by modifying allele frequencies (the proportion of members carrying a particular variant of a gene). High rates of gene flow can reduce the genetic differentiation between the two groups, increasing homogeneity. Gene flow has b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Genetic Divergence
Genetic divergence is the process in which two or more populations of an ancestral species accumulate independent genetic changes ( mutations) through time, often leading to reproductive isolation and continued mutation even after the populations have become reproductively isolated for some period of time, as there is not any genetic exchange anymore. In some cases, subpopulations cover living in ecologically distinct peripheral environments can exhibit genetic divergence from the remainder of a population, especially where the range of a population is very large (see parapatric speciation). The genetic differences among divergent populations can involve silent mutations (that have no effect on the phenotype) or give rise to significant morphological and/or physiological changes. Genetic divergence will always accompany reproductive isolation, either due to novel adaptations via selection and/or due to genetic drift, and is the principal mechanism underlying speciation. On a m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
American Mastodon
American(s) may refer to: * American, something of, from, or related to the United States of America, commonly known as the "United States" or "America" ** Americans, citizens and nationals of the United States of America ** American ancestry, people who self-identify their ancestry as "American" ** American English, the set of varieties of the English language native to the United States ** Native Americans in the United States, indigenous peoples of the United States * American, something of, from, or related to the Americas, also known as "America" ** Indigenous peoples of the Americas * American (word), for analysis and history of the meanings in various contexts Organizations * American Airlines, U.S.-based airline headquartered in Fort Worth, Texas * American Athletic Conference, an American college athletic conference * American Recordings (record label), a record label that was previously known as Def American * American University, in Washington, D.C. Sports teams S ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Woolly Mammoth
The woolly mammoth (''Mammuthus primigenius'') is an extinct species of mammoth that lived from the Middle Pleistocene until its extinction in the Holocene epoch. It was one of the last in a line of mammoth species, beginning with the African ''Mammuthus subplanifrons'' in the early Pliocene. The woolly mammoth began to diverge from the steppe mammoth about 800,000 years ago in Siberia. Its closest extant relative is the Asian elephant. The Columbian mammoth (''Mammuthus columbi'') lived alongside the woolly mammoth in North America, and DNA studies show that the two Hybrid (biology), hybridised with each other. Mammoth remains were long known in Asia before they became known to Europeans. The origin of these remains was long debated and often explained as the remains of legendary creatures. The mammoth was identified as an extinct elephant species by Georges Cuvier in 1796. The appearance and behaviour of the woolly mammoth are among the best studied of any Prehistory, prehi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Asian Elephant
The Asian elephant (''Elephas maximus''), also known as the Asiatic elephant, is the only living ''Elephas'' species. It is the largest living land animal in Asia and the second largest living Elephantidae, elephantid in the world. It is characterised by its long Elephant trunk, trunk with a single finger-like processing; large tusks in males; laterally folded large ears and wrinkled grey skin that is partly depigmented on the trunk, ears or neck. Adult males average in weight and females . It has a large and well developed neocortex of the brain, is highly intelligent and self-aware being able to display behaviours associated with grief, learning and greeting. Three subspecies are recognised—''Sri Lankan elephant, E. m. maximus'', Indian elephant, ''E. m. indicus'' and ''Sumatran elephant, E. m. sumatranus''. The Asian elephant is distributed in the Indian subcontinent and Southeast Asia, from India in the west to Borneo in the east, and Nepal in the north to Sumatra in th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nuclear DNA
Nuclear DNA (nDNA), or nuclear deoxyribonucleic acid, is the DNA contained within each cell nucleus of a eukaryotic organism. It encodes for the majority of the genome in eukaryotes, with mitochondrial DNA and plastid DNA coding for the rest. It adheres to Mendelian inheritance, with information coming from two parents, one male and one female—rather than matrilineally (through the mother) as in mitochondrial DNA. Structure Nuclear DNA is a nucleic acid, a polymeric biomolecule or biopolymer, found in the nucleus of eukaryotic cells. Its structure is a double helix, with two strands wound around each other, a structure first described by Francis Crick and James D. Watson (1953) using data collected by Rosalind Franklin. Each strand is a long polymer chain of repeating nucleotides. Each nucleotide is composed of a five-carbon sugar, a phosphate group, and an organic base. Nucleotides are distinguished by their bases: purines, large bases that include adenine and gu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phylogenetic
In biology, phylogenetics () is the study of the evolutionary history of life using observable characteristics of organisms (or genes), which is known as phylogenetic inference. It infers the relationship among organisms based on empirical data and observed heritable traits of DNA sequences, protein amino acid sequences, and morphology. The results are a phylogenetic tree—a diagram depicting the hypothetical relationships among the organisms, reflecting their inferred evolutionary history. The tips of a phylogenetic tree represent the observed entities, which can be living taxa or fossils. A phylogenetic diagram can be rooted or unrooted. A rooted tree diagram indicates the hypothetical common ancestor of the taxa represented on the tree. An unrooted tree diagram (a network) makes no assumption about directionality of character state transformation, and does not show the origin or "root" of the taxa in question. In addition to their use for inferring phylogenetic pa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
