Open Access. Powered by Scholars. Published by Universities.®

Biology Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 8 of 8

Full-Text Articles in Biology

Fluidity And Inconstancy: Australian Bush Tomatoes As An Exemplar Of Non-Normative Sex Expression, Christopher T. Martine Jun 2023

Fluidity And Inconstancy: Australian Bush Tomatoes As An Exemplar Of Non-Normative Sex Expression, Christopher T. Martine

Faculty Journal Articles

Solanum, a genus of ~1500 global species, is one of the more interesting plant groups in which to study reproductive biology and ecology. Overwhelmingly, species in this group express full cosexuality, where individual plants have flowers containing both fully-functioning “male” (staminate) and “female” (carpellate) organs. However, there have been multiple and widespread evolutionary transitions within the genus to non-normative variations on this ancestral condition. Australian bush tomatoes (ca. 40 species) are especially diverse in this regard, with uncommon variation and combinations of unisexuality and cosexuality -- including, most notably, two sexual systems known as dioecy (unisexual male or female …


Cleaning The Variable Mess: A Population Genomics Approach To Understanding The Evolutionary History Of A Complicated Plant Group, Claire Marino Jan 2023

Cleaning The Variable Mess: A Population Genomics Approach To Understanding The Evolutionary History Of A Complicated Plant Group, Claire Marino

Honors Theses

The Solanum dioicum clade is a group of Australian bush tomatoes consisting primarily of species native to Western Australia and the Northern Territory whose species delimitations tend to be quite unclear. Since David Symon’s monograph A Revision of the Genus Solanum in Australia was published in 1981, little additional progress has been made in clarifying these relationships. In this project, a population genomics approach was used to analyze the relationships and delimitations between three species within the S. dioicum clade: Solanum dioicum, S. carduiforme, and S. ossicruentum. The use of population genomics methods is advantageous to understanding …


Ecological Correlates With Dioecy In The Flora Of A Tropical Premontane Wet Forest In Costa Rica., Breanne Held Apr 2017

Ecological Correlates With Dioecy In The Flora Of A Tropical Premontane Wet Forest In Costa Rica., Breanne Held

Undergraduate Distinction Papers

There is a considerable disagreement about the selective forces that have led to the evolution of dioecy (i.e., the condition of having separate male and female flowers on separate plants). Historically, selection to enforce outcrossing has been the primary explanation despite there being little empirical evidence. Hence, many scientist argue that the selection of dioecy is driven by ecological traits that influence male and female fitness and seed dispersal. The objective of this study was to examine the association between plant sexual system (particularly, dioecy) with various ecological traits for the flora of a tropical premontane wet forest in Costa …


Dioecious Plants: Evolution And Sex Ratio And Asepen Decline, Jordan P. Sinclair Jan 2012

Dioecious Plants: Evolution And Sex Ratio And Asepen Decline, Jordan P. Sinclair

Wayne State University Dissertations

Although dioecious species are rare in nature, the sexual system appears in a diverse number of families and across all life forms and global locations. We looked at the population dynamics of natural populations to determine why many dioecious populations display biased sex ratios. We also looked at the role incestuous matings, seed and pollen dispersal patterns, and compensation play in the evolution of this sexual system using two theoretical models we developed. Finally, we studied aspen populations in the Midwest to determine how climate variables affect growth and decline. We found many dioecious species display male biased ratios and …


Growth Rates, Survivorship, And Sex Ratios Of Juniperus Virginiana On The New Jersey Piedmont From 1963 To 2000, James A. Quinn, Scott J. Meiners Jan 2004

Growth Rates, Survivorship, And Sex Ratios Of Juniperus Virginiana On The New Jersey Piedmont From 1963 To 2000, James A. Quinn, Scott J. Meiners

Faculty Research & Creative Activity

Growth rates, survivorship, and sex ratios of Juniperus virginiana on the New Jersey Piedmont from 1963 to 2000. J. Torrey Bot. Soc. XXX:000–000. 20XX.—Studies of the growth, survival, and sex ratios of dioecious species have been predominantly short-term. This research investigated growth rates, survivorship, and sex ratios among cohorts of Juniperus virginiana L. from 1963 through 2000. Males (M) and females (F) in six old-fields of different ages on the New Jersey Piedmont were analyzed, starting with the initial data on height and sex expression collected by John Small on labeled recruits from 1963 through 1976. These plants were relocated …


Growth Rates, Survivorship, And Sex Ratios Of Juniperus Virginiana On The New Jersey Piedmont From 1963 To 2000, James A. Quinn, Scott J. Meiners Jan 2004

Growth Rates, Survivorship, And Sex Ratios Of Juniperus Virginiana On The New Jersey Piedmont From 1963 To 2000, James A. Quinn, Scott J. Meiners

Scott J. Meiners

Growth rates, survivorship, and sex ratios of Juniperus virginiana on the New Jersey Piedmont from 1963 to 2000. J. Torrey Bot. Soc. XXX:000–000. 20XX.—Studies of the growth, survival, and sex ratios of dioecious species have been predominantly short-term. This research investigated growth rates, survivorship, and sex ratios among cohorts of Juniperus virginiana L. from 1963 through 2000. Males (M) and females (F) in six old-fields of different ages on the New Jersey Piedmont were analyzed, starting with the initial data on height and sex expression collected by John Small on labeled recruits from 1963 through 1976. These plants were relocated …


Growth Rates, Survivorship, And Sex Ratios Of Juniperus Virginiana On The New Jersey Piedmont From 1963 To 2000, James Quinn, Scott Meiners Jan 2004

Growth Rates, Survivorship, And Sex Ratios Of Juniperus Virginiana On The New Jersey Piedmont From 1963 To 2000, James Quinn, Scott Meiners

Faculty Research & Creative Activity

Growth rates, survivorship, and sex ratios of Juniperus virginiana on the New Jersey Piedmont from 1963 to 2000. J. Torrey Bot. Soc. XXX:000–000. 20XX.—Studies of the growth, survival, and sex ratios of dioecious species have been predominantly short-term. This research investigated growth rates, survivorship, and sex ratios among cohorts of Juniperus virginiana L. from 1963 through 2000. Males (M) and females (F) in six old-fields of different ages on the New Jersey Piedmont were analyzed, starting with the initial data on height and sex expression collected by John Small on labeled recruits from 1963 through 1976. These plants were relocated …


Simultaneous Hermaphroditism And Sexual Selection, Eric Charnov May 1979

Simultaneous Hermaphroditism And Sexual Selection, Eric Charnov

Biology Faculty & Staff Publications

Theory about the evolution of sexual behavior in dioecious species is based on the general assumption that egg production is limited by a female's ability to garner resources to make eggs, not by a lack of sperm to fertilize them. Reproductive success for males is thus limited by access to females (and their eggs). I suggest that egg production by simultaneous hermaphrodites also obeys this principle--that fertilized egg production by an individual is not limited by sperm availability, but by resources allocated to eggs. If true, this suggests that sperm competition (reproduction success through male function) and a form of …