Apis mellifera capensis
Encyclopedia
Apis mellifera capensis, the Cape honey bee or Cape
bee is a southern South Africa
n subspecies of the Western honey bee.
They are unique among honey bee subspecies because workers can lay diploid, female eggs, by means of thelytoky
, while workers of other subspecies (and, in fact, unmated females of virtually all other eusocial insects) can only lay haploid, male eggs. Not all workers are capable of thelytoky- only those expressing the thelytoky phenotype, which is controlled by a recessive allele at a single locus (workers must be homozygous at this locus to be able to reproduce by thelytoky).
In 1990 beekeeper
s transported Cape honey bees into northern South Africa, where they don't occur naturally. This has created a problem for the region's A. m. scutellata
populations. Reproducing diploid females without fertilization bypasses the eusocial insect hierarchy; an individual more related to her own offspring than to the offspring of the queen will trade in her inclusive fitness
benefits for individual fitness benefits of reproducing her own young.
This opens up the possibility of social parasitism: if a female worker expressing the thelytokous phenotype from a Cape honey bee colony can enter a colony of A. m. scutellata, she can potentially take over that African bee colony. A behavioral consequence of the thelytoky phenotype is queen pheromonal mimicry, which means the parasitic workers can sneak their eggs in to be raised with those from the African bees, and their eggs aren't policed by the African bee workers because they're similar to the African bee queen's eggs. As a result the parasitic A. m. capensis workers increase in number within a host colony, while numbers of the A. m. scutellata workers that perform foraging duties (A. m. capensis workers are greatly under-represented in the foraging force of an infected colony) dwindle, owing to competition in egg laying between A. m. capensis workers and the queen, and to the eventual death of the queen. This causes the death of the colony upon which the capensis females depended, so they will then seek out a new host colony.
Cape of Good Hope
The Cape of Good Hope is a rocky headland on the Atlantic coast of the Cape Peninsula, South Africa.There is a misconception that the Cape of Good Hope is the southern tip of Africa, because it was once believed to be the dividing point between the Atlantic and Indian Oceans. In fact, the...
bee is a southern South Africa
South Africa
The Republic of South Africa is a country in southern Africa. Located at the southern tip of Africa, it is divided into nine provinces, with of coastline on the Atlantic and Indian oceans...
n subspecies of the Western honey bee.
They are unique among honey bee subspecies because workers can lay diploid, female eggs, by means of thelytoky
Thelytoky
Thelytoky comes from the Greek thely, meaning "female", and tokos, meaning "birth". Thelytokous parthenogenesis is a type of parthenogenesis in which females are produced from unfertilized eggs. It is rare in the animal kingdom and has only been reported in about 1500 species...
, while workers of other subspecies (and, in fact, unmated females of virtually all other eusocial insects) can only lay haploid, male eggs. Not all workers are capable of thelytoky- only those expressing the thelytoky phenotype, which is controlled by a recessive allele at a single locus (workers must be homozygous at this locus to be able to reproduce by thelytoky).
In 1990 beekeeper
Beekeeper
A beekeeper is a person who keeps honey bees for the purposes of securing commodities such as honey, beeswax, pollen, royal jelly; pollinating fruits and vegetables; raising queens and bees for sale to other farmers; and/or for purposes satisfying natural scientific curiosity...
s transported Cape honey bees into northern South Africa, where they don't occur naturally. This has created a problem for the region's A. m. scutellata
African bee
The African honey bee is a subspecies of the Western honey bee. It is native to central and southern Africa, though at the southern extreme it is replaced by the Cape honey bee, Apis mellifera capensis....
populations. Reproducing diploid females without fertilization bypasses the eusocial insect hierarchy; an individual more related to her own offspring than to the offspring of the queen will trade in her inclusive fitness
Inclusive fitness
In evolutionary biology and evolutionary psychology, the inclusive fitness of an organism is the sum of its classical fitness and the number of equivalents of its own offspring it can add to the population by supporting others...
benefits for individual fitness benefits of reproducing her own young.
This opens up the possibility of social parasitism: if a female worker expressing the thelytokous phenotype from a Cape honey bee colony can enter a colony of A. m. scutellata, she can potentially take over that African bee colony. A behavioral consequence of the thelytoky phenotype is queen pheromonal mimicry, which means the parasitic workers can sneak their eggs in to be raised with those from the African bees, and their eggs aren't policed by the African bee workers because they're similar to the African bee queen's eggs. As a result the parasitic A. m. capensis workers increase in number within a host colony, while numbers of the A. m. scutellata workers that perform foraging duties (A. m. capensis workers are greatly under-represented in the foraging force of an infected colony) dwindle, owing to competition in egg laying between A. m. capensis workers and the queen, and to the eventual death of the queen. This causes the death of the colony upon which the capensis females depended, so they will then seek out a new host colony.