42x60 Horizontal Poster

1
Desiccation Tolerance Phylogeny and
Phylogeography Kristin Jenkins,
Shaily Menon, and Gabriella Pinter
NESCent, Grand Valley State University,
University of Wisconsin - Milwaukee
Results
Methods
Introduction

• Desiccation tolerant in vascular plants
• Seeds
• Pollen
• Spores
• Osmotic stress

A representation of the Maxent model for
Anastatica hierochuntica can be seen in
Figure 5. Warmer colors show areas with better
predicted conditions. White dots show the
presence locations used for training.

• Occurrence data for Anastatica hierochuntic
• Downloaded from the Global Biodiversity
  Information Facility (gbif.org).
• Of 127 available occurrence points, only 68 were
  georeferenced with latitude and longitude
  information.
• Environmental layers
• Precipitation and temperature from the IPCC
  climate dataset
• Niche Modeling
• Maximum Entropy (Maxent)
• Maxent principle is to estimate the probability
  distribution such as the spatial distribution of
  a species.
• Maxent uses entropy as the means to generalize
  specific observations of presence of a species,
  and does not require absence points

• Desertification is a sustainability problem
• 40 of the earths surface is affected
• 38 of the worlds population is affected
• These are areas of low productivity due to
• lack of water
• depletion of soil
• loss of soil
• delicate systems

Figure 1. Tortula ruralis. Source Wikimedia.org.
Figure 2. Selaginella lepidophylla
http//en.wikipedia.org/wiki/FileRose_of_Jericho.
gif

• Desiccation tolerant plants
• Survive dehydration
• Survive in dormant state for extended time
  period
• Survive rehydration

• Examples of desiccation tolerance species
  include
• Xerophyta humilis
• Tortula ruralis
• Selaginella lepidophyllla
• Anastatica hierochuntica

Figure 5. Maxent model for Anastatica
hierochuntica.

• Anastatica hierochuntica
• Family Brassicaceae
• Common Name Rose of Jericho
• Distributional range includes Northern Africa
  (Algeria, Egypt) and Asia (Arabian peninsula
  Bahrain, Kuwait, Oman, Qatar, Saudi Arabia, UAE,
  Yemen, and Western Asia Iran, Iraq, Israel,
  Jordan, Syria
• Most famous tumble weed, Palestinian tumble
  weed, resurrection plant
• After rainy season, plant dries up, leaves drop
  and branches curl into a tight ball, and dies
• Wetted again in rainy season, the ball uncurls,
  fruit opens, and disperses the seeds, which
  germinate within hours if enough water is
  available

Figure 3a. Evolution of desiccation tolerance.
Source Oliver et al. 2000 Plant Ecology.
References
Oliver et al. 2000. The evolution of desiccation
tolerance in land plants. Plant
Ecology. Phillips et al. 2006. Maximum entropy
modeling of species geographic distributions.
Ecological Modeling.
Figure 4. Rainfall Volume. Source GapMinder.org.

• We tested the following hypothesis
• Exploration of the phylogeography will enhance
  ongoing molecular phylogeny studies on the
  evolutionary relationships of desiccation
  tolerant plants

Figure 3b. Convergent evolution of desiccation
tolerance among vascular plants. Source Oliver
et al. 2000 Plant Ecology.