PARTHENOGENESIS INVESTIGATION OF THE F1 GENERATION FROM A CROSS BETWEEN DAPHNIA PULEX TEX 23 (MALES) AND TEX 85 (FEMALES)

Abstract

Daphnia pulex is a species of Daphnia that is capable of both cyclic and obligate parthenogenesis. In this experiment, two cyclically parthenogenetic (CP) isolates are crossed to access the frequency of obligately parthenogenetic (OP) offspring that will be produced. If OP animals are produced at a significant frequency from a CP-CP cross, the ‘why’ behind it must be examined. Prior research revealed that OP animals produced from CP isolates are genetically linked through introgression from a sister species, Daphnia pulicaria. This may be relevant to the results and serve as a focal point when researching the implications of them. The mating between Tex 23 (male) and Tex 85 (sexual female) isolates created new daphnia clones. To establish clonal lines, the newly hatched neonates were gathered and kept in different habitats. It was the ephippia produced by each clone that was dissected to determine the parthenogenesis of the clone. The results showed that two out of eight crosses yielded an OP clone. There was no variation within clones. The results were conclusive so statistical analysis proved redundant. With this discovery, an investigation into the introgression with D. pulicaria can be explored. After that connection is confirmed, a gene map can be curated to examine the particular gene(s) responsible for this variation.