Most of insects are dioecious, reproduce sexually by mating and lay eggs. However, as a group they have developed many other reproductive Polyembryony asexual reproduction. Sexual reproduction involves the participation of specialized sexual cells or gametes originated in the sexual organs by meiosis. It is the most common type of reproduction among arthropods and insects. In amphygony, two types of gametes are generated, which lead to the formation of the embryo once they fuse.
Most of amphygonic insects are unisexual or dioecious, so each organism generates only one type of gamete.
In fact, only a few cases in which a single organism generates more than one type of gamete hermaphroditism are currently known ; i. Icerya purchasi HemipteraPerla marginata Plecoptera and several species of the family Termitoxenidae Diptera. In dioecious organisms, the fusion of the gametes takes place once they find a mate. Insects develop diverse and complex strategies to find a proper mate: Once they get a mate, courtship usually takes place ; however, only successful courtships end in copulation.
Courtship behavior and strategies include the performance of nuptial dancesgifts i. In some cases, females will not mate with the male if he does not possess a wide territor y or a suitable food source. In the following video, we enjoy the honeybee nuptial flight:.
The fertilization or syngamy is the process through which the gametes fuse Polyembryony asexual reproduction form the embryo. This process takes place both in dioecious and hermaphrodite organisms. When mating, males usually transmit his gametes spermatozoa directly to the female body, inside which male gametes meet with the female ones ovules. In some insects and related groups, fertilization does not need a direct contact of male and female sexual organs external fertilization.
In this case, males produce a spermatophorea packet or capsule Polyembryony asexual reproduction sperm, manufactured by the accessory glands of the male reproductive system; it is usually covered by a lipoprotein film that prevents it from dehydration. Usually, the spermatophore is considered an intermediate step between aquatic and terrestrial reproduction.
Sometimes, the male produces a spermatophore and leaves it over a surface, waiting the female to take it as in Collembola ; in other groups, the male offers it directly Polyembryony asexual reproduction the female as a nuptial giftor leads the female where it has been deposited Zygentoma and Archaeognatha.
Internal fertilization is considered an evolutive adaptation to terrestrial life.
Parthenogenesis is the generation of offspring through unfertilized eggs. Usually, parthenogenesis is classified among asexual reproductive strategies; however, it is more like a special type of sexual reproduction since female gametes generated by meiosis are involved in the process. Moreover, depending on the chromosomic number of the ovule, parthenogenesis can be:. Sometimes, parthenogenesis occurs in immature stages larval or pupal.
In the pedogensis or paedogensisPolyembryony asexual reproduction forms can generate offspring by parthenogenesis; it takes place in gall midges Diptera and in a species of beetle, Macromalthus debilisamongst others. It must not be confused "Polyembryony asexual reproduction" neotenyin which a larva develops traits and reproductive structures typical of an adult as occurs in some scale bugs. In the asexual reproduction, the generation of offspring occurs without the participation of any type of gamete.
It is very uncommon in insects, being represented only by a single and odd strategy called polyembryony. Polyembryony is the phenomenon of two or more embryos developing from a single fertilized egg by scission. Even though it takes place an initial fertilization, offspring is generated asexually.
It occurs just in a few species of gall midges and in a few chalcidid hymenopterans parasitoidsthrough which they undergo population explosions. There exist different strategies through which insects generate their offspring:. Oviparous insects lay eggs. It is the most common reproductive strategy. Fertilized eggs are Polyembryony asexual reproduction inside the reproductive ducts of the female.
It happens in some cockroaches, aphids, scale bugs and flies Muscidae, Calliphoridae and Tachinidaein some beetles and trips Thysanoptera. The eggs hatch immediately before or after being laid.
Females give birth to larvae.
There exist different types of viviparity in insects:. In this video of Neil Bromhall, we can see a Polyembryony asexual reproduction of aphids giving birth:.
In this video of Geoffrey M. Who said that the a sexual life of insects was simple? Do you know any curious data? Leave your comments below! Discover them through this article! Types of reproduction Sexual reproduction Sexual reproduction involves the participation of specialized sexual cells or gametes originated in the sexual organs by meiosis. Amphygony In amphygony, two types of gametes are generated, which lead to the formation of the embryo once they fuse. Icerya purchasi left; picture property of Vijay Cavale, CC 3.
Finding mate and courtship In dioecious organisms, the fusion of the gametes takes place once they "Polyembryony asexual reproduction" a mate.
In the following video, we can enjoy the honeybee nuptial flight: Fertilization The fertilization or syngamy is the process through which the gametes fuse to form the embryo. Grasshoppers of the species Romalea microptera from Polyembryony asexual reproduction United States, mating. Picture property of http: External fertilization In some insects and related groups, fertilization does not need a direct contact of male and female sexual organs external fertilization.
Sminthurus viridis Collembola ; behind, the spermatophore. Orthoptera female grabbing the spermatophore laid by a male. Parthenogenesis Parthenogenesis is the generation of offspring through unfertilized eggs.
Bombyx mori silkworm butterfly.