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Knowledge and Skills Statement

Organisms and environments. The student knows how system are organized and function to support the health of an organism and how trait are inherited.

a classification of organisms whose cells are eukaryotic (have a nucleus and organelles), do not have cell walls, and rely on consuming other organisms for food

when an organism produces more individuals of its species by means other than the mixing of DNA from more than one 'parent;' each offspring is identical to its parent and no variation in traits occurs

the specific variations in the characteristics of organisms received from a parent or ancestor by genetic transmission

the product of sexual or asexual reproduction

an individual form of life, such as a plant, animal, bacterium, protist, or fungus; a body made up of organs, organelles, or other parts that work together to carry on the various processes of life

a classification of organisms whose cells are eukaryotic (have a nucleus and organelles), have a cell wall, and which uses chlorophyll to make their own food through photosynthesis from sunlight, water, and carbon dioxide

a group of interbreeding organisms of the same species within an environment

when two organisms share DNA in order to produce more individuals of their species; each offspring has more than one 'parent' and are genetically distinct from each parent and each other due to genetic recombination that occurs during meiosis and from fertilization

regularly interacting or interdependent group of items forming a unified whole

Research

 Tabata, Jun, Ryoko T. Ichiki, Hirotaka Tanaka, Daisuke Kageyama. Sexual versus Asexual Reproduction: Distinct Outcomes in Relative Abundance of Parthenogenetic Mealybugs following Recent Colonization. PLoS One 11, no 6 (2016 Jun): e0156587. https://doi.org/10.1371/journal.pone.0156587

Summary: Asexual reproductioni s assumed to confer advantages over sexual reproduction, which includes a “cost of males.” Sexual reproduction largely predominates in animals, however, indicating that this cost is outweighed by the genetic and/or ecological benefits of sexuality. But the evolution of sexual reproduction remains unclear, because we have limited examples that demonstrate the relative success of sexual lineages in the face of competition from asexual lineages in the same environment. Here we investigated a sympatric occurrence of sexual and asexual reproduction in the pineapple mealybug, Dysmicoccus brevipes. Our recent censuses demonstrated that on Okinawa sexually reproducing individuals can coexist with and even dominate asexual individuals in the presence of habitat and resource competition. Co-existence of the two lineages cannot be explained by the results of laboratory experiments, which showed that the intrinsic rate of increase in the sexual lineage was not obviously superior to that of the asexual lineage. Differences in biotic and/or abiotic selective forces operating on the two islands might be the cause of this discrepancy. This biological system offers a unique opportunity to assess the relative success of sexual versus asexual lineages with an unusual morphology and life cycle.