Topic
Cardinalis
About: Cardinalis is a research topic. Over the lifetime, 74 publications have been published within this topic receiving 1860 citations.
Papers published on a yearly basis
Papers
TL;DR: The results suggest that ecological factors resulting from adaptive divergence are the primary isolating barriers in this system of Mimulus lewisii and M. cardinalis, sister species of monkeyflowers.
Abstract: Evolutionists have long recognized the role of reproductive isolation in speciation, but the relative contributions of different reproductive barriers are poorly understood. We examined the nature of isolation between Mimulus lewisii and M. cardinalis, sister species of monkeyflowers. Studied reproductive barriers include: ecogeographic isolation; pollinator isolation (pollinator fidelity in a natural mixed population); pollen competition (seed set and hybrid production from experimental interspecific, intraspecific, and mixed pollinations in the greenhouse); and relative hybrid fitness (germination, survivorship, percent flowering, biomass, pollen viability, and seed mass in the greenhouse). Additionally, the rate of hybridization in nature was estimated from seed collections in a sympatric population. We found substantial reproductive barriers at multiple stages in the life history of M. lewisii and M. cardinalis. Using range maps constructed from herbarium collections, we estimated that the different ecogeographic distributions of the species result in 58.7% reproductive isolation. Mimulus lewisii and M. cardinalis are visited by different pollinators, and in a region of sympatry 97.6% of pollinator foraging bouts were specific to one species or the other. In the greenhouse, interspecific pollinations generated nearly 50% fewer seeds than intraspecific controls. Mixed pollinations of M. cardinalis flowers yielded >75% parentals even when only one-quarter of the pollen treatment consisted of M. cardinalis pollen. In contrast, both species had similar siring success on M. lewisii flowers. The observed 99.915% occurrence of parental M. lewisii and M. cardinalis in seeds collected from a sympatric population is nearly identical to that expected, based upon our field observations of pollinator behavior and our laboratory experiments of pollen competition. F1 hybrids exhibited reduced germination rates, high survivorship and reproduction, and low pollen and ovule fertility. In aggregate, the studied reproductive barriers prevent, on average, 99.87% of gene flow, with most reproductive isolation occurring prior to hybrid formation. Our results suggest that ecological factors resulting from adaptive divergence are the primary isolating barriers in this system. Additional studies of taxa at varying degrees of evolutionary divergence are needed to identify the relative importance of pre- and postzygotic isolating mechanisms in speciation.
682 citations
TL;DR: Using both multivariate and univariate regression techniques, selection acting through female reproductive success is measured in two hermaphroditic species with precise pollen placement but different pollinators: hummingbird‐pollinated Lobelia cardinalis and bumblebee‐ pollinated L. siphilitica.
Abstract: Using both multivariate and univariate regression techniques, I measured selection acting through female reproductive success in two hermaphroditic species with precise pollen placement but different pollinators: hummingbird-pollinated Lobelia cardinalis and bumblebee-pollinated L. siphilitica. Six traits were analyzed in two populations of L. cardinalis and one population of L. siphilitica: flower number, mean number of flowers open per day, inflorescence height, number of days in flower, median-flower date and nectar-stigma distance. In another study it was found that female reproductive success in one population of L. cardinalis was much less pollen limited than in the other two populations, and it was therefore expected that selection of female reproductive traits in this population would be weaker. In the univariate analyses correlations caused nearly all traits to have significant directional selection coefficients. However, in the multivariate analyses no traits in L. siphilitica experienced directional or quadratic selection. Selection acted differently in the two L. cardinalis populations. The less pollen-limited population experienced positive directional selection on flower number and median-flower date, while in the other L. cardinalis population there was positive directional selection on flower number and nectar-stigma distance and both positive directional and positive quadratic selection on height. The functional significance of floral traits in these two species and the probable effect of increased sample sizes are discussed.
217 citations
TL;DR: The Barsine cardinalis-anomala 'species-complex' is revised, and six new species-groups are established, with a new combination and new synonymy.
Abstract: The Barsine cardinalis–anomala 'species-complex' is revised. Five new species ( B. pseudocardinalis Volynkin & Cerný, sp. nov. from Indochina, B. fansipana Volynkin & Cerný, sp. nov. from North Vietnam, B. nangkwak Volynkin & Cerný, sp. nov. from North Thailand, B. incompletostriga Volynkin & Cerný, sp. nov. from North-East India and B. rawanga Volynkin & Cerný, sp. nov. from North Burma) and one new subspecies ( B. cardinalis gemina Volynkin & Cerný, ssp. nov. from North Thailand) are described. A new combination ( Barsine anomala (Elwes, 1890), comb. nov. ), new synonymy ( Barsine cardinalis cardinalis (Hampson, 1900) = Miltochrista erubescens Rothschild, 1936, syn. nov.), and six new species-groups are established. Adults, male and female genitalia of all species are illustrated.
125 citations
TL;DR: It is proposed that there was no loss of genetic diversity in areas colonized after the Last Glacial Maximum because recent high-levels of gene flow across the region have homogenized genetic Diversity in eastern North America.
Abstract: Earth history events such as climate change are believed to have played a major role in shaping patterns of genetic structure and diversity in species. However, there is a lag between the time of historical events and the collection of present-day samples that are used to infer contemporary population structure. During this lag phase contemporary processes such as dispersal or non-random mating can erase or reinforce population differences generated by historical events. In this study we evaluate the role of both historical and contemporary processes on the phylogeography of a widespread North American songbird, the Northern Cardinal, Cardinalis cardinalis. Phylogenetic analysis revealed deep mtDNA structure with six lineages across the species' range. Ecological niche models supported the same geographic breaks revealed by the mtDNA. A paleoecological niche model for the Last Glacial Maximum indicated that cardinals underwent a dramatic range reduction in eastern North America, whereas their ranges were more stable in Mexico. In eastern North America cardinals expanded out of glacial refugia, but we found no signature of decreased genetic diversity in areas colonized after the Last Glacial Maximum. Present-day demographic data suggested that population growth across the expansion cline is positively correlated with latitude. We propose that there was no loss of genetic diversity in areas colonized after the Last Glacial Maximum because recent high-levels of gene flow across the region have homogenized genetic diversity in eastern North America. We show that both deep historical events as well as demographic processes that occurred following these events are critical in shaping genetic pattern and diversity in C. cardinalis. The general implication of our results is that patterns of genetic diversity are best understood when information on species history, ecology, and demography are considered simultaneously.
76 citations
Related Topics (5)
Performance Metrics
| Year | Papers |
|---|---|
| 2021 | 1 |
| 2020 | 4 |
| 2017 | 4 |
| 2016 | 1 |
| 2015 | 3 |
| 2013 | 2 |