In placental mammals, offspring are born as juveniles: complete animals with the sex organs present although non-functional. After several months or years, the sex organs develop further to maturity and the animal becomes sexually mature. Most female mammals are only fertile during certain periods and during those times, they are said to be "in heat". At this point, the animal is ready to mate. Individual male and female mammals meet and carry out copulation. For most mammals, males and ...

See also:

Sexual reproduction, Sexual reproduction - Sexual reproduction of protists and fungi, Sexual reproduction - Reproduction in flowering plants, Sexual reproduction - Reproduction in reptiles, Sexual reproduction - Reproduction in birds, Sexual reproduction - Reproduction in mammals, Sexual reproduction - The mammalian male, Sexual reproduction - The mammalian female, Sexual reproduction - Gestation, Sexual reproduction - Birth, Sexual reproduction - Monotremes, Sexual reproduction - Marsupials, Sexual reproduction - Origin of Sexual Reproduction

Read more here: » Sexual reproduction: Encyclopedia II - Sexual reproduction - Reproduction in mammals

See also:

Biological reproduction, Biological reproduction - Asexual reproduction, Biological reproduction - Sexual reproduction, Biological reproduction - Mitosis and Meiosis, Biological reproduction - Reproductive strategies, Biological reproduction - Asexual vs. sexual reproduction, Biological reproduction - The Red Queen hypothesis, Biological reproduction - Life without reproduction, Biological reproduction - Mechanical reproduction

Read more here: » Biological reproduction: Encyclopedia II - Biological reproduction - Sexual reproduction

Sexual reproduction is a biological process by which organisms create descendants that have a combination of genetic material contributed from two (usually) different members of the species. Each of two parent organisms contributes half of the offspring's genetic makeup by creating haploid gametes. Most organisms form two different types of gametes. In these anisogamous species, the two sexes are referred to as male (producing sperm or microspores) and female (producing ova or megaspores). In isogamous species the ...

See also:

Biological reproduction, Biological reproduction - Asexual reproduction, Biological reproduction - Sexual reproduction, Biological reproduction - Mitosis and Meiosis, Biological reproduction - Reproductive strategies, Biological reproduction - Asexual vs. sexual reproduction, Biological reproduction - The Red Queen hypothesis, Biological reproduction - Life without reproduction

Read more here: » Biological reproduction: Encyclopedia II - Biological reproduction - Sexual reproduction

Parthenogenesis (Partheno-genesis from the Greek παρθενος, "virgin", + γενεσις, "birth") means the growth and development of an embryo or seed without fertilization by a male. Parthenogenesis occurs naturally in some lower plants (called agamospermy), invertebrates (e.g. water fleas, aphids) and some vertebrates (e.g. lizards, salamanders, some fish, and even turkeys). Parthenogenetic populations are typically all-female. As with all types of asexual reproduction, there are bo ...

Including:

• Parthenogenesis - Asexual versus sexual reproduction
• Parthenogenesis - Parthenogenesis
• Parthenogenesis - Gynogenesis
• Parthenogenesis - Hybridogenesis

Read more here: » Parthenogenesis: Encyclopedia - Parthenogenesis

Biological reproduction is the biological process by which new individual organisms are produced. Reproduction is a fundamental feature of all known life; each individual organism exists as the result of reproduction by an antecedent. The known methods of reproduction are broadly grouped into two main types: sexual and asexual reproduction. In asexual reproduction, an individual can reproduce without involvement with another individual of that species. The division of a bacterial cell into two daughter cells is an example of as ...

Including:

• Biological reproduction - Asexual reproduction
• Biological reproduction - Sexual reproduction
• Biological reproduction - Mitosis and Meiosis
• Biological reproduction - Reproductive strategies
• Biological reproduction - Asexual vs. sexual reproduction
• Biological reproduction - The Red Queen hypothesis
• Biological reproduction - Life without reproduction
• Biological reproduction - Mechanical reproduction

Read more here: » Biological reproduction: Encyclopedia - Biological reproduction

Sexual intercourse or coitus is the human form of copulation. The term sexual intercourse refers to a wider range of sexual activities than the term coitus, which only refers to male-female genital sex. See Human sexual behavior for a discussion of the broader sense of sexual intercourse and List of sexual positions for the wide variety of sexual activities that exist. See the terms frot for male-male genital sex and tribadism for female-female genital sex. "Genital sex" as used here re ...

Including:

• Sexual intercourse - Sexual reproduction
• Sexual intercourse - Sex evolving beyond reproduction
• Sexual intercourse - Sexual drive
• Sexual intercourse - Downside of sexual intercourse
• Sexual intercourse - Sexual problems
• Sexual intercourse - Sexual morality and legality

Read more here: » Sexual intercourse: Encyclopedia - Sexual intercourse

Class Polychaeta (paraphyletic?) Class Clitellata    Oligochaeta - Earthworms and others    Acanthobdellida    Branchiobdellida    Hirudinea - Leeches Class Myzostomida Class Archiannelida (polyphyletic) Class Echiura The annelids, collectively called Annelida (from Latin annellus "little ring"), are a large phylum of animals, comprising the segmented worms, with about 15 000 modern species including th ...

Including:

• Annelid - Anatomy
• Annelid - Reproduction
• Annelid - Asexual reproduction
• Annelid - Sexual reproduction
• Annelid - Fossil record
• Annelid - Relationships
• Annelid - Classes and subclasses of Annelida

Read more here: » Annelid: Encyclopedia - Annelid

Copulation is the union of the external sexual organs of two sexually reproducing animal organisms for insemination and for subsequent internal fertilization, which is fertilization of ova inside organisms. The two organisms may be of opposite sexes or hermaphroditic, as is the case with, for example, snails. Animals initially lived only in water and reproduced by external fertilization in the water. Certain animals st ...

Read more here: » Copulation: Encyclopedia - Copulation

Sex, in the scope of this article and category, refers to the male and female duality of biology and reproduction. The somewhat similar term gender has more to do with identity than biology. The concept is confined to organisms that reproduce sexually. The female sex is defined as the one which produces the larger gamete (i.e., reproductive cell) and which typically bears the offspring. The category of sex reflects the biological reproductive function, rather than sexaulity or other behaviors. In some lower animals, sex may be assigned to specific structures rather than the entire organism as some species, such a ...

Including:

• Sex - Sex in non-animal species
• Sex - Sex among humans
• Sex - Discordance
• Sex - Biological varieties of discordance
• Sex - Psychological behavioral and cultural varieties of discordance
• Sex - Social and legal considerations

Read more here: » Sex: Encyclopedia - Sex

See also: Human sexuality Biological reproduction Gender Sex Other related archivesBiological reproduction, Gender, Human sexuality, Sex

Read more here: » Sexuality: Encyclopedia - Sexuality

The Bottlenose Dolphin (Tursiops truncatus) is the most common and well-known dolphin species. It inhabits warm and temperate seas worldwide and may be found in all but the Arctic and the Antarctic Oceans. Bottlenose Dolphin - Physical description. Bottlenose Dolphins are grey, varying from dark grey at the top near the dorsal fin to very light grey and almost white at the underside. This makes them hard to see both from above and below when swimming. The elongated upper and lower jaws ...

Including:

• Bottlenose Dolphin - Physical description
• Bottlenose Dolphin - Behavior and life
• Bottlenose Dolphin - Diet
• Bottlenose Dolphin - Senses and communication
• Bottlenose Dolphin - Tool use and culture
• Bottlenose Dolphin - Sexuality and reproduction
• Bottlenose Dolphin - Natural predators
• Bottlenose Dolphin - Taxonomy
• Bottlenose Dolphin - Conservation
• Bottlenose Dolphin - Bottlenose Dolphins and humans
• Bottlenose Dolphin - Bottlenose Dolphins in fiction

Read more here: » Bottlenose Dolphin: Encyclopedia - Bottlenose Dolphin

Asexual reproduction (also known as agamogenesis) is the simplest form of reproduction and does not involve meiosis, gamete formation, or fertilization. In laymen's terms, there is only one "parent" involved. This form of reproduction is common among simple organisms such as amoeba and other single-celled organisms, although most plants produce asexually as well (see vegetative reproduction). Because it does not require male and female participation, asexual reproduction occurs faster than sexual reproduction and ...

Including:

• Asexual reproduction - Advantages and disadvantages

Read more here: » Asexual reproduction: Encyclopedia - Asexual reproduction

The Wolffian duct (also known as archinephric duct, Leydig's duct, and the mesonephric duct) is a paired organ found in mammals including humans during embryogenesis. It connects the primitive kidney Wolffian body (or mesonephros) to the cloaca and serves as the anlage for certain male reproductive organs. In a male, it develops into a system of connected organs between the testis and the prostate, namely the rete testis, the efferent ducts, the epididymis, the vas deferens, the seminal vesicle, and ...

Read more here: » Wolffian duct: Encyclopedia - Wolffian duct

Coitus is the basic reproductive method of humans. During ejaculation, which normally accompanies male orgasm, a series of muscular contractions delivers semen containing male gametes known as sperm cells or spermatozoa into the vault of the vagina. The subsequent route of the sperm from the vault of the vagina, is through the cervix and into the uterus, and thence into the fallopian tubes. Millions of sperm are present in each ejaculation, to increase the chances of one fertilizing an egg or ovum. Sperm cells can survive up to nine days in ...

See also:

Sexual intercourse, Sexual intercourse - Sexual reproduction, Sexual intercourse - Sex evolving beyond reproduction, Sexual intercourse - Sexual drive, Sexual intercourse - Downside of sexual intercourse, Sexual intercourse - Sexual problems, Sexual intercourse - Sexual morality and legality

Read more here: » Sexual intercourse: Encyclopedia II - Sexual intercourse - Sexual reproduction

Organisms that reproduce through asexual reproduction tend to grow in number exponentially. However, because they rely on mutation for variations in their DNA, all members of the species have similar vulnerabilities. Organisms that reproduce sexually yield a smaller amount of offspring, but the large amount of variation in their genes makes them less susceptible to disease. Many organisms can reproduce sexually as well as asexually. Aphids, slime molds, sea anemones and many plants are examples. When environmental factors are favorabl ...

See also:

Biological reproduction, Biological reproduction - Asexual reproduction, Biological reproduction - Sexual reproduction, Biological reproduction - Mitosis and Meiosis, Biological reproduction - Reproductive strategies, Biological reproduction - Asexual vs. sexual reproduction, Biological reproduction - The Red Queen hypothesis, Biological reproduction - Life without reproduction, Biological reproduction - Mechanical reproduction

Read more here: » Biological reproduction: Encyclopedia II - Biological reproduction - Asexual vs. sexual reproduction

Organisms that reproduce through asexual reproduction tend to grow in number exponentially. However, because they rely on mutation for variations in their DNA, all members of the species have similar vulnerabilities. Organisms that reproduce sexually yield a smaller amount of offspring, but the large amount of variation in their genes makes them less susceptible to disease. Many organisms can reproduce sexually as well as asexually. Aphids, slime molds, sea anemones and many plants are examples. When environmental factors are favorabl ...

See also:

Biological reproduction, Biological reproduction - Asexual reproduction, Biological reproduction - Sexual reproduction, Biological reproduction - Mitosis and Meiosis, Biological reproduction - Reproductive strategies, Biological reproduction - Asexual vs. sexual reproduction, Biological reproduction - The Red Queen hypothesis, Biological reproduction - Life without reproduction

Read more here: » Biological reproduction: Encyclopedia II - Biological reproduction - Asexual vs. sexual reproduction

Humans, bonobos and notably dolphins are all animals known to have non-reproductive sex, apparently for the sake of pleasure. All three animals engage in heterosexual intercourse even when the female is not in estrus, that is, at a point in her reproductive cycle suitable for successful impregnation. Likewise, all three animals engage in homosexual behaviors. That is not to say that homosexuality and non-reproductive heterosexuality are limited to these three species; rather ...

See also:

Sexual intercourse, Sexual intercourse - Sexual reproduction, Sexual intercourse - Sex evolving beyond reproduction, Sexual intercourse - Sexual drive, Sexual intercourse - Downside of sexual intercourse, Sexual intercourse - Sexual problems, Sexual intercourse - Sexual morality and legality

Read more here: » Sexual intercourse: Encyclopedia II - Sexual intercourse - Sex evolving beyond reproduction

The male has two slits at the bottom side of the body: one hiding the penis and further behind one for the anus. The female has one genital slit, housing the vagina and the anus. Courtship behavior of the male includes clinging along to that female, posing for the female, stroking, rubbing, nuzzling, mouthing, jaw clapping, and yelping. Coitus is preceded by lengthy foreplay; then the two animals arrange belly to belly, the penis extends out of its slit and is inserted into the vagina. The act lasts only 10-30 seconds, but i ...

See also:

Bottlenose Dolphin, Bottlenose Dolphin - Physical description, Bottlenose Dolphin - Behavior and life, Bottlenose Dolphin - Diet, Bottlenose Dolphin - Senses and communication, Bottlenose Dolphin - Tool use and culture, Bottlenose Dolphin - Sexuality and reproduction, Bottlenose Dolphin - Natural predators, Bottlenose Dolphin - Taxonomy, Bottlenose Dolphin - Conservation, Bottlenose Dolphin - Bottlenose Dolphins and humans, Bottlenose Dolphin - Bottlenose Dolphins in fiction

Read more here: » Bottlenose Dolphin: Encyclopedia II - Bottlenose Dolphin - Sexuality and reproduction

Asexuality is relatively rare among multicellular organisms, for reasons that are not completely understood. Current hypotheses suggest that, while asexual reproduction may have short term benefits when rapid population growth is important or in stable environments, over the long term sexual reproduction offers a net advantage by allowing more rapid adaptation to changing environments. Asexual lineages can increase their numbers rapidly because (since individuals are always female) everyone can produce viable eggs. In sexual populations some ...

See also:

Parthenogenesis, Parthenogenesis - Asexual versus sexual reproduction, Parthenogenesis - Parthenogenesis, Parthenogenesis - Gynogenesis, Parthenogenesis - Hybridogenesis

Read more here: » Parthenogenesis: Encyclopedia II - Parthenogenesis - Asexual versus sexual reproduction

The male has two slits at the bottom side of the body: one hiding the penis and further behind one for the anus. The female has one genital slit, housing the vagina and the anus. Courtship behavior of the male includes clinging along to that female, posing for the female, stroking, rubbing, nuzzling, mouthing, jaw clapping, and yelping. Coitus is preceded by lengthy foreplay; then the two animals arrange belly to belly, the penis extends out of its slit and is inserted into the vagina. The act lasts only 10-30 seconds, but i ...

See also:

Bottlenose Dolphin, Bottlenose Dolphin - Physical description, Bottlenose Dolphin - Behavior and life, Bottlenose Dolphin - Diet, Bottlenose Dolphin - Senses and communication, Bottlenose Dolphin - Cognition, Bottlenose Dolphin - Tool use and culture, Bottlenose Dolphin - Sexuality and reproduction, Bottlenose Dolphin - Natural predators, Bottlenose Dolphin - Taxonomy, Bottlenose Dolphin - Conservation, Bottlenose Dolphin - Bottlenose Dolphins and humans, Bottlenose Dolphin - Bottlenose Dolphins in fiction

Read more here: » Bottlenose Dolphin: Encyclopedia II - Bottlenose Dolphin - Sexuality and reproduction