Me at Zion National park over spring break

Undergraduate Mentoring in

Environmental Biology:

Jill Romero

My study site near Red Mountain, Northern Arizona


Ontogeny is the visual and physical variation that results from changes in gene expression.   Basically the results of ontogeny can be seen in aging. 

Lawrence, et al 2000

A prime example of ontogenetic variation can be seen in this eucalyptus image.  The upper zone represents the mature zone, and is noticeably different than the lower zone, which represents the juvenile zone.

Pinyon arthropods:

The types of insects on my pinyons will include critters like mites, ants, and spiders.  Identifying them will be the most laborious part of my research, but luckily I have a great lab group to help me out.   


Pinyon ontogeny and arthropod community

I am working with Dr. Thomas G. Whitham and his research team.  Our team consists of two graduate students, Crescent Scudder and Adrian Stone, and one other undergraduate student, Judy Schmutz.  We are focusing on how environmental stresses affect arthropod communities.  My project centers around a common Flagstaff tree, Pinyon pines, and the wonderful world of insects.  I am currently studying how a pinyon's ontogeny, or aging, affect the resulting arthropod community.  I am examining both juvenile and mature pinyons and measuring their respective arthropod species richness, species abundance, and community composition.

The site that I am working on is located near Red Mountain in Northern Arizona, approximately 45 minutes out of Flagstaff.   Here the habitat is relatively homogeneous to reduce the affects of environmental variables on my samples.  This site has some very healthy pinyons compared to some other sites we checked out, which exhibited high pinyon mortality.  The soil is a cinder composition and all of the trees are on a South facing slope.   I am sampling 30 juvenile trees and 30 mature trees.  My mature trees  will also include samples from  the lower portion of the tree, the male zone, and the upper portion of the tree, the female zone.  My samples will be collected once the trees begin to pollinate, which theoretically results in a larger grouping of insects.  Once the samples are collected, they will be placed in labeled freezer bags and stored in the lab freezer.

The collected samples will then be sorted out with a low powered microscope.  Once the arthropods have been sorted out of branch debris, we will then try to identify them as low down the taxonomic ladder as possible.  Statistical procedures will then be carried out to determine the differences or similarities in communities on these different aged pinyons. 

My project is important because insects are near the base of our terrestrial food web, and it is therefore imperative that we see how different factors, such as ontogeny, affect their communities.  My project will help forest management projects and will also aid in  pinpointing how environmental stresses, which can in turn influence pinyon mortality rates,  affect arthropods.  As our climate continues to change, we must look at how these changes will affect  ecosystems before it is too late.


Ontogenetic areas that will be sampled:

A juvenile pinyon

The male zone on a mature pinyon


The female zone on a mature pinyon on a pin