My enrichment project for the summer of 2012 involved two research projects that employed distinct techniques in animal behavior research. On the island of Ometepe, Nicaragua I designed and implemented a study in which I used field research methods to examine the effect of male Howler Monkey affiliations on subordinate male participation in howling displays. After returning to the states, I collaborated with Dr. Cusato on a research project at Centre College. In this study we utilized a conditioned place preference (CPP) paradigm to test the reinforcing properties of a species-specific vocalization, the male separation call, on male and female Japanese quail. Through my exposure to both field and laboratory methods in animal behavior, I acquired an appreciation for the advantages and disadvantages of each discipline and the necessity of conducting both types of research to gain a more holistic understanding of many essential questions in animal behavior.

1. Exploring Different Techniques in Animal Behavior
Josh Rieskamp, Centre College
Abstract
My enrichment for the summer of 2012 involved two research projects that
employed two distinct techniques in animal behavior research. On the island of
Ometepe, Nicaragua, I designed and implemented a study in which I used field research
Male Mantled Howler Monkeys on Ometepe Island, Nicaragua
methods to examine the effect of male mantled howler affiliations on subordinate male Male (left) and Female (right) Japanese quails
Photo from www.scienceblogs.com
Photo Credit: Colleen Friedly participation in howling displays. After returning to the states, I collaborated with Dr.
Mantled Howler Monkey (Alouatta palliata) Field Study Cusato to test the reinforcing properties of a species-specific vocalization, the male Japanese Quail (Coturnix japonica) Laboratory Experiment
separation call, on male and female Japanese quails using a conditioned place
Background preference (CPP) paradigm. Through my exposure to both field and laboratory methods Background
On the island of Ometepe, Nicaragua, the rising sun is accompanied by the roars in animal behavior, I acquired an appreciation for the advantages and disadvantages of In a previous study, Dr. Cusato collaborated with students to determine
of mantled howler monkeys (Alouatta palliata) echoing down the slopes of Vulcan each discipline and the necessity of conducting both types of research to gain a more whether male Japanese quails could learn to become more efficient at mating
Maderas. These vocal displays can be intimidating when members of a group howl holistic understanding of many essential questions in animal behavior. from a species-specific stimulus paired with the presence of a female. The
cooperatively, as has been observed during standoffs between rival groups (Wang and species-specific stimulus was the male separation call, a vocalization produced
Milton, 2003). Interestingly, there is variation in terms of individual participation Mantled Howler Field Study by male Japanese quails when they are separated from a female before mating
within a group during howling displays, ranging from only a single male howling to all can occur. Using a biologically relevant stimulus like the separation call as
Procedure opposed to an arbitrary stimulus helps take into account an organism’s ecology
members of the group participating (Kitchen et al., 2004). Additionally, studies have
I collected data for three groups of mantled howlers living in two forests at
revealed differences in the level of cooperative howling between two mantled howler Ometepe over a period of five days during the rainy season, from June 7, 2012 to June (the environment in which behaviors undergo selective pressures) that laboratory
groups of similar size and composition ( Dias et al., 2009). 11, 2012. I conducted 10 minute focal samples on all adult males in each group, studies often fail to simulate (Timberlake, 1983).
These differences in the contributions of individuals to howling displays likely recording at 30 second intervals the behavior of the focal subject, the identity and My study will be used in conjunction with this study to examine the
result from an assessment of the potential costs of participation versus those of estimated proximity of the focal subject’s nearest neighbor, and the focal subject’s reinforcing properties of the separation call using a conditioned place preference
proximity from the alpha male. Simultaneously to focal sample collection, I conducted (CPP) paradigm.
nonparticipation. Participation in howling is energetically demanding and can even
all-occurrence instantaneous scan samples for every observed bout of howling in which
become deadly during encounters between groups when it reveals the vocalizer’s I recorded the estimated proximity from the alpha male and participation or Procedure
position to members of the rival group (Kitchen et al., 2004). Conversely, participation nonparticipation in howling for all adult males in the group. Subjects: Twelve male and twelve female Japanese quails with the same
in howling may actually deter physical fights between groups and can result in the hatch dates were chosen from a stock bred at Centre College.
successful defense of food resources if an individual’s participation gives its group a
Results Pre-test: Each of the subjects was allowed to move freely about the
numeric advantage over the opponent group (Kitchen et al., 2004). Furthermore, strong conditioned place preference apparatus for 5 minutes to determine a
baseline preference for one context or the other.
cooperative howling displays can successfully repel takeover attempts by single
Training: For each of the six training days, each of the subjects was
immigrant males or coalitions of males that would impose fitness costs on resident exposed to one of the contexts in the morning and the other context in
males through infanticide or monopolizing access to reproductive females (Dias et al., the afternoon. The context for which the subject displayed a baseline
2009). preference was paired for five minutes with the 20 Hz tone and the other
As dominant mantled howler males often have exclusive access to estrous females context was paired for five minutes with the separation call.
Testing: At the end of the six day training phase, subjects were allowed
(Wang & Milton, 2003), the cost of nonparticipation in howling should be higher for
to move freely about the conditioned place preference (CPP) apparatus
dominant males than for subordinate males. Therefore, alpha males are expected to for five minutes. The time spent in each context was recorded.
contribute more to group defense. However, alpha males may allow subordinate males
to mate with group females. With a genetic investment in the group, subordinate males
CPP Apparatus
are more likely to aid in group defense (Wang & Milton, 2003). Studies have also
suggested that subordinate males are more likely to participate in howling displays
when there is a high degree of familiarity between the alpha male and the subordinate
(Kitchen et al., 2004; Dias et al., 2009).
Therefore, subordinate males should be more likely to howl if they have close
affiliations with the alpha male and less likely to howl if they do not. Using spatial Implications
proximities within a group as an indicator of affiliations (Wang and Milton, 2003), Subordinate males that maintained a closer average proximity to
subordinate males should participate in a higher percentage of howling displays if they the alpha male participated in a greater percentage of howling displays.
maintain closer spatial proximities to the alpha male and participate in a lower These results support the hypothesis that subordinate males are more
likely to howl if they have a close affiliation with the alpha male and are
percentage of howling displays if they keep their distance from the alpha male.
less likely to howl if they do not and corroborate previous studies
suggesting that familiarity among males results in a greater amount of References
Dias, P.A.D., Rangel-Negrin, A., Veá, J.J., and Canales-Espinosa, D. (2009). Coalitions and male-male
cooperative howling.
behavior in Alouatta palliata. Primates, 51:91-94.
A possible explanation for familiarity among males leading to Kitchen, D.M., Horwich, R.H., and James, R.A. (2004). Subordinate male black howler monkey (Alouatta
greater cooperative howling is that long-term affiliations with the alpha pigra) responses to loud calls: experimental evidence for the effects of intra-group male relationships
male may allow subordinate males to mate with group females and thus and age. Behaviour, 141: 703-723.
become genetically invested in group defense. It is therefore imperative Timberlake, W. (1983). The Functional Organization of Appetitive Behavior: Behavior Systems and
for future studies to incorporate genetic tests to assess the roles of Learning. Zeiler, M.D. and Harzem, P. (eds.). Advances in Analysis of Behavior: Biological Factors in
Learning (Vol. 3). (pp. 177-221) New York: John Wiley and Sons.
kinship and paternity in male mantled howler affiliations. Wang, E. and Milton, K. (2003). Intragroup social relationships of male Alouatta palliata on Barro
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