Friends, family, or fellow researchers are sometimes curious about the work that I do. Rather than make them read the reprint of a published article (dry, boring, no photos), for which nobody has time anyway, I offer this medium as a way to quickly describe what the "gist" of a paper was, and show a slide or two about the study organism I worked on. I hope that this approach will help increase the appeal of my work and make it more accessible to a broader audience.

Below I provide a few slides, and the main message of the paper in a "nut-shell" for each of the following references. You can also go directly to the information pertaining to a specific paper by simply clicking on it.

1) Schlaepfer, M.A. 1998. Use of a fluorescent powder marking technique on small terrestrial anurans. Herpetological Review 29:25-26. Reprint (pdf file)

2) Schlaepfer, M.A. and R. Figeroa-Sandí 1998. Female reciprocal calling in Eleutherodactylus podiciferus. Copeia 1998:1076-1080. Reprint (pdf file)

3) Schlaepfer, M.A. and J. McNeil 2000. Are virgin male lepidopterans more successful in mate acquisition than previously mated individuals? A study of the European corn borer, Ostrinia nubilalis (Lepidoptera: Pyralidae). Canadian Journal of Zoology 78:2045-2050. Reprint (pdf file)

4) Schlaepfer, M.A. and T.A. Gavin (in press). Edge effects on frogs and lizards in tropical forest fragments. Conservation Biology.

For reprint of this article, click here. (Requires Adobe Acrobat)

The paper in a nutshell:
    Nobody likes cutting toes, which is the traditional method for individually marking amphibians and reptiles for ecological studies. So before I began my Master's, I wanted to test the feasibility of alternative marking methods. I consulted the literature, the most promising technique seemed to be a fluorescent powder, which was blasted on to the skin of the animal using a pressurized air source. Other researchers had used this technique with success on salamanders, and found that marks lasted over a year.
    I conducted a field test to see if the method would work on the small leaf litter frogs (Eleutherodactylus podiciferus) I wanted to mark. I found that the fluorescent powder marking technique was more expensive, less convenient, and appeared to do much more harm to the animals than toe clipping. (Harm was done primarily when the blast of air accidentally blew the little frogs away, literally, or when powder got in to the frog's mouth). The usefulness of the fluorescent powder method may have been limited by the small size of my study species (average adult size is less than 2 cm). In subsequent studies, I therefore marked individuals with toe clipping.
 
 

Photo of an adult female Eleutherodactylus podiciferus, in a "mirror box". This females measures about 2 cm in length. Note the yellow spot of fluorescent powder on her right thigh, applied using the described technique.

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For reprint of article click here. (Requires Adobe Acrobat)

The paper in a nut-shell:
    In most frog species, the male will call to try and get a female's attention so that he can mate with her. But in some species, including Eleutherodactylus podiciferus, females will respond to a calling male with a call of her own. This unusual phenomenon is called female reciprocal calling.
    The existence of female reciprocal calling is interesting for two reasons: (1) most people, including herpetologists, often assume that a calling frog is a male frog. There are at least 14 published studies to date describing frog species with female-reciprocal calling, so clearly this is not always the case. This suggests that female calling could be very wide spread and has simply been overlooked in many cases, because of our (male) biases. (2) Species of frogs that exhibit female reciprocal calling appear to live in ecological conditions where it may be difficult for a female to locate a mate. For example, many of the described species live in very diffuse populations and have long breeding seasons. In other described species, males take care of the eggs, and thus may be the limiting sex. This suggests that female reciprocal calling may be an important adaptation for species living under these circumstances.
 
 

	An adult female Eleutherodactylus podiciferus. This species lives in the leaf litter of rainforest in Costa Rica. Diffuse populations may make finding a mate more difficult, and thus may have favored the evolution of female calling.
	Eleutherodactylus podiciferus eggs are not laid in water, but directly in the moist leaf litter, where they complete their development! From the eggs emerge tiny froglets (see image). This unusual ability to by-pass the tadpole stage (called direct development) has freed species of this genus from the need to congregate around bodies of water to reproduce, and probably contributed to their huge evolutionary success (there are 600+ species in this genus).
	A preserved male (left) and female (right) Eleutherodactylus podiciferus, and a clutch of 3 eggs. The reciprocal calling between this pair was recorded and is described in the paper. Both individuals were placed in a bag overnight. I found eggs in the bag the next morning, providing pretty good evidence that one of the two was actually a female. These individuals were deposited at the University of Costa Rica, San Jose, as voucher specimens.

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For reprint of article click here. (Requires Adobe Acrobat)

The paper in a nut-shell:
    European corn borers are small moths, that (surprise, surprise) bore in to corn. An interesting aspect of their biology is that once the male moth emerges from the pupal stage, it has a finite amount of sperm to utilize. Males are never sure how many times they are going to mate, so they ejaculate a lot of sperm on their first go, and decreasing amounts on subsequent matings. A male that has already mated 3 times will produce so little sperm that the receiving female will produce significantly fewer eggs than had she mated with the virgin.
    I was an undergrad at the time I conducted this research (as part of a summer internship at Laval University, in Quebec City) and so I asked: well, given the choice between a full-to-brim-with-sperm virgin, and a sperm-depleted Don Juan, females should prefer the virgins, right? Wrong. In 40 mate-choice experiments, significantly more females mated with the experienced male rather than the virgin males. This paper described this unusual result, and looks in to some of the possible explanations why. Were the experienced males better lovers? Possibly. The experienced males, by virtue of having successfully managed to mate 3 previous times, may have also been above-average quality males. We measured quality by comparing the area of the left and right wing of each moth (the idea being that higher quality males will have more symmetrical wings) and found indeed that experienced males had above-average symmetry in their wings. So females may have been choosing to mate with the experienced males because they were of above-average quality, independently (or unaware) of how sperm-depleted these males were.
 

A male European Corn Borer, Ostrinia nubilalis.

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The paper in a nut-shell:
    Natural habitats throughout the world are becoming increasingly fragmented by human activities (see photo below). Human-altered habitats, like cow-pastures, tend to be sunnier, windier, and drier than adjacent forests, and thus may cause so many changes in the adjacent natural habitat that many species are no longer able to survive within the forest areas near the edges. And this is bad.
    As part of my Master's work that I conducted in Las Cruces, Costa Rica, I wanted to see if I could find some generalized response of lizards and frogs to such "edge effects", and if they would be negative, as is often assumed. I did this by comparing many pairs of plots, where one plot was always right near the forest-pasture edge, and the other one was far from the edge. Thus, on average, the difference between many such pairs of plots should reflect the influence of the edge-effects on various species of lizards and frogs. I found that some frog species tended to avoid edges. Others seemed indifferent to their presence. Some lizard species were more abundant along edges during some seasons, and avoided them during others. This paper was of interest to conservation biologists for three reasons: 1) it is among a very small number of studies that provides actual data on the effects of edges on amphibians and reptiles. To date there has been a lot of theory and speculation, but little hard data to confirm it. 2) It illustrates the complexity of edge effects: each species probably has its own biological requirements, and how each species responds to the presence of a given edge will probably be highly variable. 3) It illustrates how edge effects are not a static process, i.e., something that enters forest fragments a given distance, but instead are something highly variable in time and space, advancing and retreating depending on topography, time of day, seasons, weather etc. In sum, nature is complex, and we don't real understand what is going on. Please provide us with more money so that we can further investigate this issue.
 

	The fragmented landscape near the Las Cruces Biological Station, in southern Costa Rica. This part of Costa Rica was completely forested as recently as 50 years ago. The large "L"-shaped forest fragment is the Las Cruces Biological Reserve.
	Norops polylepis One of the common lizards species found in Las Cruces. This lizard was more abundant near edges in the dry season, but less so in the wet season. Sometimes edge effects can be good: lizards near edges had many fewer parasites (chiggers) than lizards deep in the forests
	Jeisson (left) and Randy Figueroa-Sandi, the two residents who have assisted me in the field over the years, standing near one of the pasture-forest edges where we worked.

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