Biological Sciences Alum Writes Children’s Book

January 27th, 2012

Professor Jim Nardi (BS ’70 from Purdue) now at the University of Illinois wrote a captivating story for children that stems from his Entomology research. Emeritus Purdue Professor Peter Waser writes this about Jim’s book…….

Alumnus James Nardi, Research Scientist at the University of Illinois, has just published “In Mouse’s Backyard” (Schiffer Publishing Co), an exploration of all those small critters, plants, and other strange, mysterious, fascinating, and sometimes creepy or squishy living things that the curious child (or parent) will likely find in any midwestern backyard. Lovely drawings are filled with surprises — inconspicuous beasties that make you realize how much it pays to look again, with your eyes a little wider open, both at the book and at the ordinary world around you. Supplemented with some lovely photos and even electron micrographs of things like stink bugs’ beaks, mushroom spores and velvet mite toes, all with the scale marked clearly, but not in the metric system — the thickness of a nickel and the width of a hair are the units here.

The text is in verse and filled with the sort of details that drew me into natural history as a kid — introducing you to everything from how mosses reproduce to what the greek words for “toe” and “feathery” tell you about beetles whose scientific names are more imposing than they are. btw, this book just may draw some readers into looking at an earlier book of Jim’s, “Life in the Soil”, a more traditional guide to all those little organisms, from tardigrades to cup fungi, that live all around us but usually escape our notice. If you’re the sort of person who’s always wondered where you could find a field guide to the slime molds, Nardi is the author for you.

Peter

Fall 2011 Doctorates

December 12th, 2011

Congratulations to Dr. Elizabeth Thiele and Dr. Jacqueline Doyle on their successful Ph.D. defenses!  Dr. Thiele has taken a research position working on a W.H.O. funded project in the Anthropology department at Purdue University.  Dr. Doyle has accepted a position as an lecturer at Purdue.

2 New Masters of Science

November 30th, 2011

Congratulations to Patrice Baumhardt and Lauren Brierley for successfully defending master’s degrees!  Lauren is now living in Raleigh, N.C. and pursuing a career in veterinary medicine.  Patrice will continue her work on avian vision and behavior as a researcher in the lab of Dr. Fernandez-Juricic here at Purdue. We wish them well in all future endeavors.

June 11th, 2010

Pelaez Lab: Graduate students and undergraduates

Vascular smooth muscle physiology and signal transduction, physiology and evolution, biology education, physiology education.

Nancy Emery

January 27th, 2010

Biological Sciences researcher wins NSF early-career award

January 8th, 2010

Krista Nichols, an assistant professor of biological sciences, will use her grant to study the genetics and evolution of migration, using rainbow and steelhead trout. The research will examine the genetic basis of ecological diversity between migrating and non-migrating animals to gain a better understanding of how ecological diversity has evolved within and among species. The work also will provide an important baseline for future studies on the effects of climate change, which has been shown to impact the migration patterns of some fish species. During the project, Nichols will work with a native Alaskan village to document migration patterns of fish and to collect genetic information for use in future studies on the role of genetics, evolution and environment on ecological diversity in migrating animals. This award is funded under the American Recovery and Reinvestment Act of 2009.

Females do it better: hearing in the brown-headed cowbird

December 8th, 2009

Megan D. Gall, a graduate student in the Ecology and Evolutionary Biology area, studies sex differences in auditory physiology in the brown-headed cowbird.  Cowbirds are strange because they do not raise their own young.  Instead  females lay their eggs in the nests of other bird species (hosts).  It has been hypothesized that females eavesdrop on sexual signals, like song, to detect, locate, cowbirds_or even determine the quality of a particular host.  This is a problem, however, because the frequency range of song in cowbirds (6-11 kHz) and their hosts (1-4 kHz) is very different.  So far we have found that cowbirds are most sensitive to frequencies in the range of host vocalizations.  Moreover, females have lower thresholds (i.e. can hear softer sounds) and have greater sensitivity than males.  This suggests that females are capable of detecting and processing distant host vocalizations.  For more information see Megan’s website: http://web.ics.purdue.edu/~mgall.

Pollen movement influences local adaptation in patchy plant populations

November 18th, 2009

A ubiquitous pattern in nature is that populations are patchy:  species are restricted to a subset of the habitats available to them. Understanding the processes that underlie these patterns is a long-standing goal in both ecology and evolutionary biology.  In an upcoming issue of the American Naturalist, a study conducted by Dr. Nancy Emery examines the role of pollen movement in restricting one particular wildflower species to vernal pool wetlands in California.  The study, conducted during the 2004-2005 growing season, represents one of the first attempts to examine the evolutionary limits to plant distribution patterns in a natural population.

California vernal pools are ephemeral wetlands that accumulate rain during the fall and winter, and dry in the spring as rain ceases and temperatures rise.  Fremont’s Goldfields (Lasthenia fremontii) are often most abundant in the deepest portions of pools and dwindle in number and size at progressively shallower positions.  Emery documented that Goldfields flower as the water recedes in the spring, yielding concentric rings of flowering plants that begin at the edge of the pool and collapse inward as spring progresses.  Thus, plants at the center of the pool likely flower much later than plants nearer the pool edge, making it difficult for pollen to move from the center to the edge of the population.  The insects that pollinate Goldfields move very locally within these flowering bands, further restricting the potential for pollen to move across the population.  A field experiment revealed that seeds generated from edge parents were less likely to germinate that seeds generated from alternative patterpollen-poolsns of pollen movement.  This study provides evidence that patterns of pollen movement relative to the environmental context can play a large role in determining the edges of species’ distributions.

Watch your back! Birds with higher visual acuity can detect predators from farther away.

November 15th, 2009

A recent study conducted in Dr. Esteban Fernandez-Juricic’s lab addressed a relevant question in predator-prey interactions: can variations in the visual system of prey influence their ability to detect a predator attack?

The Authors investigated how predator detection and vigilance European-starlingbehavior are related to how far away (visual acuity) and how far around the head (visual coverage) two bird species (European starlings and house sparrows) could perceive objects visually. European starlings can detect objects at greater distances but have less visual coverage (e.g., a larger blind spot at the rear of their heads) than house sparrows. The Authors found that House sparrows reduced their chances of detecting the predator from farther distances compared to European starlings; which could be related to their lower visual acuity. However, the probabilities of predator detection of both species decreased with body positions and head orientations with lower visual coverage despite the between-species differences. European starlings had longer vigilance bouts probably to enhance visual coverage, whereas house sparrows had higher vigilance rates likely to update information about potential predators more often.

These results suggest that sensory systems can play an important role in predator detection, and eventually in the evolution of behavioral, morphological, or physiological strategies to avoid predation. 

This paper has been recently published in Behavioral Ecology (Volume 20, Pages: 936-945, 2009).

Birds’ selective fall hearing may hold lessons for humans

November 13th, 2009

black_capped_chickadeeIt appears that some birds have found a simple solution when they are not looking for a mate in the fall – they just ignore love’s call by muting their hearing.

Purdue University biologists studying how both birds and humans adapt to noise have found that some bird species have degraded hearing ability in the fall – when it’s not mating season – as well as in other select situations. The findings have potential implications for hearing loss in humans, said Jeffrey Lucas, a Purdue professor of biological sciences.

“We’ve been thinking a lot about human hearing,” Lucas said. “The world is getting noisier as the environment gets more urbanized. Noise becomes much more important to understand.”

In ongoing research, Lucas is looking at how birds adapt the precision of their hearing to seasonal changes as well as to disturbances in their environment. His work even goes so far as to suggest hearing ability differs between the sexes.

Read more: http://news.uns.purdue.edu/x/2009b/091103LucasAuditory.html