Ceratina calcarata
Ceratina calcarata, the spurred ceratina, is a species of small carpenter bee in the family Apidae. It is found in eastern North America. This species ranges from Georgia, USA north to Ontario, Canada and east to Nova Scotia, Canada. This bee is a common generalist, native pollinator, it pollinates plants like watermelon and cucumber very effectively. C. calcarata adds to the productivity of a wide range of ecological and agricultural systems due to its wide range and abundance. This small bee is becoming a model organism in the scientific research of social evolution. C. calcarata is the first subsocial bee species to have its genome published, allowing researchers to investigate the evolutionary origins of social behaviour.
Reproduction
Male eggs are laid on provision masses that are smaller than those that female eggs are laid on. Based on the size of the mother's provision masses, there is a positive association between her size and her foraging capabilities; however, more daughters are not produced by larger mothers as it might be assumed. Larger offspring are more beneficial for C. calcarata because the progeny are more likely to survive the winter months, resulting in an indirect increase in fecundity since the more bees that survive the colder months will be able to procreate and increase the potential number of grand-offspring.Cuticle hydrocarbons are used to indicate reproductive status and age in C. calcarata; the fertility signal is the hydrocarbon pentacosane. Since the reproductive signal has been discovered, those signals have likely developed the queen bee's pheromones. Typically in eusocial insects, the queen uses pheromonal influence to subdue daughter/worker reproduction; however, in the subsocial Ceratina calcarata, pre-dispersal females have fully developed ovaries and are capable of laying eggs, but they have no chance at becoming fertilized. They are about to enter diapause and will have no chance at having offspring this season, and therefore, queen maternal overexpression of pentacosane is not required for the suppression in offspring regulation.
It has been hypothesized that this bee can use chemical profiles to distinguish between different individuals. This means that based on the chemicals that a particular bee emits, other C. calcarata can tell the difference among specific nest members and non-nest members.
Interbreeding with ''Ceratina dupla''
Females of C. calcarata and C. dupla look nearly identical; however, the males are dissimilar. The degree of development of a metafemoral tooth is the most visible trait that distinguishes males of the two species. Although interbreeding only occurs in nature where they are sympatric, viable offspring have been produced between these two species of bees. Furthermore, C. calcarata and C. dupla mate at such low rates that they should be treated as two distinct species despite having morphologically exact females.Maternal Care
Ceratina calcarata is a subsocial bee, meaning that there is extended care of the offspring and prolonged interaction between parent and offspring; however, there are no other interactions between individuals of this species except for mating. Females clean and defend their progeny into adulthood. C. calcarata mothers will feed their newly enclosed offspring twice, which is a behaviour known as called dual-phase pollen provisioning and is typically not observed in all bees. This double feeding most likely helps ensure the youngs' survival during their diapause throughout the winter season. Females create social relationships with their parents and a single generation of children, with the eldest dwarf daughter foraging and feeding her siblings. This dwarf daughter isn't consistently reared in all nests, but when she is, it's thought that she serves as a form of brood insurance during the second phase when the mother bee is unable to give adequate care and provision for her enclosed young.Mother bees help their offspring develop peaceful behaviours, whereas bees who grow up as orphans are more likely to be violent and aggressive.
Adult size is directly correlated to the quantity of food the individual received as a larva; in order to produce successful female offspring, the mother bee must do more work foraging compared to the work needed to produce male offspring. This is due to the female bee's greater size than their male counterpart. Daughters are roughly 8% larger than sons and 11% smaller than their mothers. Larger bees are more likely to survive the winter and initiate their own successful nests for the next season.