Abstract Detail

Pteridology

Watkins, James E. [1], Campany, Courtney [2], Lawson, Evelyn [2].

A preliminary investigation into the physiology of fern sperm: focus on longevity, velocity, and competition. .

Ferns represent an intriguing lineage of vascular plants that rely on motile swimming sperm that are largely dispersed by water. Work emerging from the Farrar lab in the late 90’s indicated that sperm could live for hours, fundamentally changing the way we think about fern reproductive ecology. To date, little work has explored sperm release time, velocity, longevity, and change in reproductive potential with swimming time. Even less well understood are the impacts that potential competitors have on sperm physiology. The goal of this work was to explore basic aspects of fern sperm behavior, specifically, we examine how velocity and longevity vary across species from epiphytic and terrestrial habitats. We then evaluate if and how sperm physiology is impacted when species are grown in the presence of Pteridium. Finally, we explore the link between swimming time and fertilization potential in a subset of species. We gathered data from 10 species and our preliminary results indicate that longevity and velocity vary markedly across species and variation within our small data set was not linked to epiphytic/terrestrial habitat. Further supporting Farrar’s discoveries, some species were indeed able to swim for over 60 min, yet many were active for less than 10 min. Velocity varied across taxa from 0.00011 miles per hour to 0.00045 miles per hour, again velocity in this small data set was not linked to epiphytic/terrestrial habit. The impact of Pteridium is complicated and in the three species tested, sperm extracted from gametophytes grown in the presence of Pteridium can either swim faster (Pteris propinqua), shorter (Salpichlaena volubilis), or exhibit no difference (Serpocaulon triseriale). Data are still being generated on the impact of swimming time and fertilization.

1 - Colgate University, Department of Biology, 13 Oak Drive, Hamilton, New York, 13346, USA
2 - Colgate University, Department of Biology, 13 Oak Drive, Hamilton, NY, 13346, United States

Keywords:
Pteridophyte
Gametophyte
reproductive ecology
Sperm Velocity
fern.

Presentation Type: Oral Paper
Session: 5, Pteridology I
Location: 108/Mayo Civic Center
Date: Monday, July 23rd, 2018
Time: 11:45 AM
Number: 5015
Abstract ID:251
Candidate for Awards:None