Understanding how new life forms originate is a central question in biology. Population divergence is usually studied with respect to how single lineages diverge into daughter taxa. However, populations may not always differentiate in isolation; divergence of one taxon could create new niche opportunities in higher trophic levels, leading to the sequential origin of many new taxa. Here, we show that this may be occurring for three species of parasitoid wasps attacking Rhagoletis fruit flies. As flies shift and adapt to new host plants, wasps follow suit and diverge in kind, resulting in a multiplicative increase of diversity as the effects of ecologically based divergent selection cascade through the ecosystem. Biodiversity therefore may potentially beget increasing levels of biodiversity.
Table 1. Collecting Sites
Collecting sites analyzed in the study
Table 2. Microsatellite Loci Details
List of microsatellites genotyped in the study and oligonucleotide primer pairs (forward and reverse) used to PCR amplify loci.
Table 3. Microsatellite allele frequencies for Utetes canaliculatus
Microsatellite allele frequencies for U. canaliculatus attacking different Rhagoletis hosts (hawthorn, apple, snowberry, and flowering dogwood flies) at nine sites designated 1-9 in the eastern U.S.
Table 4. Microsatellite Allele Frequencies for Diachasmimorpha mellea
Microsatellite allele frequencies for D. mellea attacking different Rhagoletis hosts (hawthorn, apple, blueberry, and black cherry flies) at at four sites designated 1, 2, 3 & 6 in the eastern U.S.
Table 5. Results From Host Fruit Odor Discrimination of D. mellea and U. canaliculatus
Results from host fruit odor discrimination assays conducted in a Y-tube olfactometer for U. canaliculatus and D. mellea.
Table 6. Results From Cross-reared D. alloeum Host Odor Discrimination
Results from host fruit odor discrimination assays conducted in a Y-tube olfactometer where individual hawthorn origin and blueberry origin D. alloeum were reared for a single generation through a non-natal apple host plant and the apple infesting host race of R. pomonella host flies
Table 7. The Site of Mating Assembly For U. canaliculatus and D. mellea.
The site of mating assembly for U. canaliculatus and D. mellea.
Table 8. Eclosion timing for flies and wasps
The number of days to eclosion following post-winter heating for different host associated populations of flies in the Rhagoletis pomonella sibling species complex and the parasitoid wasps that attack the flies (U. canaliculatus and D. mellea).
Table 9. Longevity Estimates for U. canaliculatus and D. mellea
Estimates of longevity of adult D. mellea and U. canaliculatus.
Table 10. Genotypes x Eclosion Timing for U. canaliculatus
Raw genotype scores for individual U. canaliculatus attacking sympatric pairs of hawthorn and apple flies across 20 loci (labeled UC08-UC061) used in two-way ANOVA's to test for associations with eclosion timing.
Table 11. Genotypes x Eclosion Timing for D. mellea
Raw genotype scores for individual D. mellea attacking sympatric pairs of hawthorn and apple flies across 21 loci (labeled DM01-DM65) used in two-way ANOVA's to test for associations with eclosion timing.