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Penile Spines
Many mammalian species have developed keratinized penile spines along the glans or shaft, which may be involved in sexual selection. These spines have been described as being simple, single-pointed structures (macaques) or complex with two or three points per spine ( strepsirrhines). Penile spine morphology may be related to mating system. Non-human mammals Felines, especially domestic cats, are well known for having penile spines. Upon withdrawal of a cat's penis, the spines rake the walls of the female's vagina, which may serve as a trigger for ovulation. Many other felid species have penile spines, but they are relatively small in jaguars and pumas, and do not occur in margays. Penile spines in chimpanzees and mice are small surface projections made by the piling up of keratinized cell layers in the outermost skin surface.Hill, W.C.O. Note on the male external genitalia of the chimpanzee. ''Proc.Zool.Soc. Lond.'' 116, 129–132 (1946) They occur in wombats, koalas, spo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Domestic Cat
The cat (''Felis catus''), also referred to as the domestic cat or house cat, is a small Domestication, domesticated carnivorous mammal. It is the only domesticated species of the family Felidae. Advances in archaeology and genetics have shown that the domestication of the cat occurred in the Near East around 7500 BC. It is commonly kept as a pet and working cat, but also ranges freely as a feral cat avoiding human contact. It is valued by humans for companionship and its ability to kill vermin. Its retractable claws are adapted to killing small prey species such as mice and rats. It has a strong, flexible body, quick reflexes, and sharp teeth, and its night vision and sense of smell are well developed. It is a social species, but a solitary hunter and a crepuscular predator. Cat intelligence is evident in their ability to adapt, learn through observation, and solve problems. Research has shown they possess strong memories, exhibit neuroplasticity, and display cognitive skil ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fossa (animal)
The fossa (''Cryptoprocta ferox''; or ; ) is a slender, long-tailed, cat-like mammal that is endemic to Madagascar. It is a member of the carnivora, carnivoran family Eupleridae. The fossa is the largest mammalian carnivore on Madagascar and has been compared to a small cougar, as it has Convergent evolution, convergently evolved many cat-like features. Adults have a head-body length of and weigh between , with the males larger than the females. It has semi-retractable claws (meaning it can extend but not retract its claws fully) and flexible ankles that allow it to climb up and down trees head-first, and also support jumping from tree to tree. A larger relative of the species, ''Cryptoprocta spelea'', probably became extinct before 1400. The species is widespread, although population density, population densities are usually low. It is found solely in forested habitat, and actively hunts both by day and night. Over 50% of its diet consists of lemurs, the endemic primates f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Felidae Anatomy
Felidae ( ) is the family of mammals in the order Carnivora colloquially referred to as cats. A member of this family is also called a felid ( ). The 41 extant Felidae species exhibit the greatest diversity in fur patterns of all terrestrial carnivores. Cats have retractile claws, slender muscular bodies and strong flexible forelimbs. Their teeth and facial muscles allow for a powerful bite. They are all obligate carnivores, and most are solitary predators ambushing or stalking their prey. Wild cats occur in Africa, Europe, Asia and the Americas. Some wild cat species are adapted to forest and savanna habitats, some to arid environments, and a few also to wetlands and mountainous terrain. Their activity patterns range from nocturnal and crepuscular to diurnal, depending on their preferred prey species. Reginald Innes Pocock divided the extant Felidae into three subfamilies: the Pantherinae, the Felinae and the Acinonychinae, differing from each other by the ossification ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lion
The lion (''Panthera leo'') is a large Felidae, cat of the genus ''Panthera'', native to Sub-Saharan Africa and India. It has a muscular, broad-chested body (biology), body; a short, rounded head; round ears; and a dark, hairy tuft at the tip of its tail. It is sexually dimorphic; adult male lions are larger than females and have a prominent mane. It is a social species, forming groups called prides. A lion's pride consists of a few adult males, related females, and cubs. Groups of female lions usually hunt together, preying mostly on medium-sized and large ungulates. The lion is an apex predator, apex and keystone predator. The lion inhabits grasslands, savannahs, and shrublands. It is usually more diurnality, diurnal than other wild cats, but when persecuted, it adapts to being active nocturnality, at night and crepuscular, at twilight. During the Neolithic period, the lion ranged throughout Africa and Eurasia, from Southeast Europe to India, but it has been reduced to fr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sexual Conflict
Sexual conflict or sexual antagonism occurs when the two sexes have conflicting optimal fitness (biology), fitness strategies concerning reproduction, particularly over the mode and frequency of mating, potentially leading to an evolutionary arms race between males and females. In one example, males may benefit from multiple matings, while multiple matings may harm or endanger females due to the anatomical differences of that species. Sexual conflict underlies the evolutionary distinction between male and female. The development of an evolutionary arms race can also be seen in the chase-away sexual selection model, which places inter-sexual conflicts in the context of secondary sexual characteristic evolution, sensory exploitation, and female resistance. According to chase-away selection, continuous sexual conflict creates an environment in which mating frequency and male secondary sexual trait development are somewhat in step with the female's degree of resistance. It has primari ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fordyce Spots
Fordyce spots (also termed Fordyce granules) are harmless and painless visible sebaceous glands typically appearing as white/yellow small bumps or spots on the inside of lips or cheeks, gums, or genitalia. They are common, and are present in around 80% of adults. Treatment is generally not required and attempts to remove them typically result in pain and scarring. Their cause is unclear, and they are not associated with hair follicles. Diagnosis is done by visualisation. They may appear similar to genital warts or molluscum. They were first described in 1896 by American dermatologist John Addison Fordyce. History Fordyce spots are named after the American dermatologist John Addison Fordyce, who first described them in 1896.Fordyce first described them in 1896. Classification Sebaceous glands are normal structures of the skin but may also be found ectopically in the mouth, where they are referred to as ''oral Fordyce granules'' or ectopic sebaceous glands. On the foreski ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bird Penis
A penis (; : penises or penes) is a sex organ through which male and hermaphrodite animals expel semen during copulation, and through which male placental mammals and marsupials also urinate. The term ''penis'' applies to many intromittent organs of vertebrates and invertebrates, but not to all. As an example, the intromittent organ of most Cephalopoda is the hectocotylus, a specialized arm, and male spiders use their pedipalps. Even within the Vertebrata, there are morphological variants with specific terminology, such as hemipenes. Etymology The word "penis" is taken from the Latin word for "tail". Some derive that from Indo-European ''*pesnis'', and the Greek word πέος = "penis" from Indo-European ''*pesos''. Prior to the adoption of the Latin word in English, the penis was referred to as a "yard". The Oxford English Dictionary cites an example of the word ''yard'' used in this sense from 1379, and notes that in his ''Physical Dictionary'' of 1684, Steven Blanka ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HCONDELs
hCONDELs refer to regions of deletions within the human genome containing sequences that are highly conserved among closely related relatives. Almost all of these deletions fall within regions that perform non-coding functions. These represent a new class of regulatory sequences and may have played an important role in the development of specific traits and behavior that distinguish closely related organisms from each other. Nomenclature The group of CONDELs of a specific organism is specified by prefixing the CONDELs with the first letter of the organism. For instance, hCONDELs refer to the group of CONDELs found in humans whereas mCONDELs and cCONDELs refer to mouse and chimpanzee CONDELs respectively. Identification of CONDELs The term hCONDEL was first used in the 2011 ''Nature'' article by McLean et al. in whole-genome comparison analysis. This involved firstly identifying a subset of 37,251 human deletions (hDELs) through pairwise comparisons of chimpanzee and macaque geno ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hominin
The Hominini (hominins) form a taxonomic tribe of the subfamily Homininae (hominines). They comprise two extant genera: ''Homo'' (humans) and '' Pan'' (chimpanzees and bonobos), and in standard usage exclude the genus '' Gorilla'' ( gorillas), which is grouped separately within the subfamily Homininae. The term Hominini was originally introduced by Camille Arambourg (1948), who combined the categories of ''Hominina'' and ''Simiina'' pursuant to Gray's classifications (1825). Traditionally, chimpanzees, gorillas and orangutans were grouped together, excluding humans, as pongids. Since Gray's classifications, evidence accumulating from genetic phylogeny confirmed that humans, chimpanzees, and gorillas are more closely related to each other than to the orangutan. The orangutans were reassigned to the family Hominidae ( great apes), which already included humans; and the gorillas were grouped as a separate tribe (Gorillini) of the subfamily Homininae. Still, details of th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hirsuties Coronae Glandis
Pearly penile papules (PPP; also known as hirsutoid papillomas or as , Latin for 'papillae of the corona of the glans') are benign, small bumps or spots on the human penis. They vary in size from 0.5-1 mm, are pearly or flesh-colored, smooth and dome-topped or filiform, and appear in one or, several rows around the corona, the ridge of the head of the penis and sometimes on the penile shaft. They are painless, non-cancerous and not harmful. The medical condition of having such papules is called hirsutoid papillomatosis or (Latin for 'papillary hirsutism of the corona of the glans'). Cause and mechanism PPPs are a type of angiofibroma. Their function is not well-understood. They are usually considered as vestigial remnants of penile spines, sensitive features found in the same location in other primates. They do not spread and often spontaneously regress. Along with Fordyce glands, PPPs secrete oils to keep the skin of the head of the penis in good condition. Smeg ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Galago
Galagos , also known as bush babies or ''nagapies'' (meaning "night monkeys" in Afrikaans), are small nocturnal primates native to continental, sub-Sahara Africa, and make up the family Galagidae (also sometimes called Galagonidae). They are considered a sister group of the Lorisidae. According to some accounts, the name "bush baby" comes from either the animal's cries or its appearance. The Ghanaian name ''aposor'' is given to them because of their firm grip on branches. In both variety and abundance, the bush babies are the most successful strepsirrhine primates in Africa, according to the African Wildlife Foundation. Taxonomic classification and phylogeny Galagos are currently grouped into six genera. '' Euoticus'' is a basal sister taxon to all the other galagids. The 'dwarf' galagids recently grouped under the genus '' Galagoides'' have been found, based on genetic data, and supported by analysis of vocalisations and morphology, to actually consist of two clad ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Copulatory Plug
A mating plug, also known as a copulation plug, vaginal plug, sperm plug, or sphragis (Latin, from , "a seal"), is a gelatinous secretion used in the mating of some species. It is deposited by a male into a female genital tract, such as the vagina, and later hardens into a plug or glues the tract together. While females can expel the plugs afterwards, the male's sperm still gets a time advantage in getting to the egg, which is often the deciding factor in fertilization. The mating plug plays an important role in sperm competition and may serve as an alternative and more advantageous strategy to active mate guarding. In some species, such a passive mate-guarding strategy may reduce selection on large male size. Such a strategy may be advantageous because it would allow a male to increase reproductive success by spending more time pursuing new female mates rather than active mate guarding. Composition The mating plug of the '' Bombus terrestris'' was chemically analyzed and fou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
