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Patterns of petiole abundance and diversity in bark beetles (Scolytinae) of Cecropia trees in Monteverde, Costa Rica

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Title:
Patterns of petiole abundance and diversity in bark beetles (Scolytinae) of Cecropia trees in Monteverde, Costa Rica
Translated Title:
Patrones de abundancia del pecíolo y diversidad de los escarabajos de corteza (Scolytinae) de los árboles de Cecropia en Monteverde, Costa Rica ( )
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English
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Gandhi, Sonali
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Subjects / Keywords:
Bark beetles--Behavior--Costa Rica--Monteverde Cloud Forest Reserve   ( lcsh )
Interspecific interactions--Cecropia   ( lcsh )
Escarabajos de corteza--Comportamiento--Costa Rica--Reserva Bosque Nuboso Monteverde
Interacciones interspecíficas--Cecropia
Tropical Ecology 2008
Interspecific competition--Cecropia
Bark beetle feeding preferences
Ecología Tropical 2008
Preferencias alimenticias del escarabajo de corteza
Competencia interspecífica--Cecropia
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Reports   ( lcsh )
Reports

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Abstract:
Cecropia trees regularly shed their woody, large petioles year round. This provides bark beetles from the family Scolytinae with a dependable and stable microhabitat. Bark beetles bore into the petioles, lay their eggs, and feed on the pith (Wood 1983). This study was conducted in Monteverde, Costa Rica. It examined the abundance and diversity of bark beetles between Cecropia polyphlebia in the Monteverde Cloud Forest (1550 meters) and an intermediary phenotype at Bajo del Tigre (1400 meters). It also investigated the percent of petioles colonized, species richness, evenness, and the influence of petiole moisture and length on the abundance and diversity of beetles. I analyzed 90 dead, woody petioles from the ground and from hanging vegetation from each site. Petioles were dissected and beetles were removed and identified by one of six Scolytinae morphospecies. Differences in the abundance and diversity of beetles between the two species were then compared. This study suggests that there was no difference in species diversity between the two tree species (p > 0.05). However, a difference in abundance between the hybrid phenotype and C. polyphlebia was observed. The hybrid phenotype possessed a higher abundance of beetles. Also moisture content (ANCOVA, F = 4.93, df = 2, p = 0.0083), the species of Cecropia (ANCOVA, F = 11.2, df = 1, p =0.001), and petiole length with Cecropia species (ANCOVA, F = 5.16, df = 1, p = 0.0244) had an influence on the abundance of beetles. The higher abundance of beetles in the hybrid phenotype could indicate differences in interspecific competition due to phenotypic traits of the Cecropia species. Differences in moisture content and petiole length between the two Cecropia species may reflect petiole preference and favorability of tree hosts. Furthermore, the higher abundance of beetles in the lower elevation hybrid phenotype could indicate that the majority of bark beetles may not be affected by climate change unlike many other species of animals and plants that are being severely impacted by the increasing temperatures.
Abstract:
Este estudio se realizó en Monteverde, Costa Rica. Examinó la abundancia y la diversidad de los escarabajos de corteza entre Cecropia polyphlebia (1550 metros) en el Bosque Nuboso de Monteverde y un fenotipo intermedio en el Bajo del Tigre (1400 metros). También investigó el porcentaje de pecíolos colonizados, riqueza de especies, igualdad y la influencia de la humedad del pecíolo y la longitud de la abundancia y diversidad de escarabajos.
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Text in English.
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Patterns of Petiole Abundance and Diversity in Bark Beetles (Scolytinae) of Cecropia trees in Monteverde, Costa Rica Sonali Gandhi Department of Biology, University of Southern India na ABSTRACT Cecropia trees regularly shed their woody, large petioles y ear round. This provides bark beetles from the family Scolytinae with a dependable and stable micr ohabitat. Bark beetles bore into the petioles, lay their eggs, and feed on the pith (Wood 1983). This study was conducted in Monteverde, Costa Rica. It examine d the abundance and diversity of bark beetles between Cecropia polyphlebia in the Monteverde Cloud Forest (1550 meters) and an intermediary phenotype at Bajo del Tigre (1400 meters). It also investigated the percent of petioles colonized, species richness, ev enness, and the influence of petiole moisture and l ength on the abundance and diversity of beetles. I analyz ed 90 dead, woody petioles from the ground and from hanging vegetation from each site. Petioles were di ssected and beetles were removed and identified by one of six Scolytinae morphospecies. Differences in the abundance and diversity of beetles between the two species were then compared. This study suggests tha t there was no difference in species diversity betw een the two tree species (p > 0.05). However, a differe nce in abundance between the hybrid phenotype and C. polyphlebia was observed. The hybrid phenotype possessed a hig her abundance of beetles. Also moisture content (ANCOVA, F = 4.93, df = 2, p = 0.0083), the species of Cecropia (ANCOVA, F = 11.2, df = 1, p =0.001), and petiole length with Cecropia species (ANCOVA, F = 5.16, df = 1, p = 0.0244) had an influence on the abundance of beetles. The higher a bundance of beetles in the hybrid phenotype could indicate differences in interspecific competition d ue to phenotypic traits of the Cecropia species. Differences in moisture content and petiole length between the two Cecropia species may reflect petiole preference and favorability of tree hosts. Furtherm ore, the higher abundance of beetles in the lower elevation hybrid phenotype could indicate that the majority of bark beetles may not be affected by cli mate change unlike many other species of animals and pla nts that are being severely impacted by the increas ing temperatures. RESUMEN Los rboles de Cecropia sueltan regularmente sus la rgos y leosos durante todo el ao. Esto proporcion a corteza escarabajos de la familia Scolytinae de un microhabitat fiable y fijo. Los escarabajos de la c orteza habitan en los pecolos, colocan sus huevos, y la c omen la mdula (Wood 1983). Este estudio fue realiz ado en Monteverde, Costa Rica. Examin la abundancia y la diversidad de escarabajos de corteza entre Cecropia polyphlebia (1550 metros) y un fenotipo in termedio en el bosque nuboso de Monteverde y un fenotipo intermedio en del de Bajo Tigre (1400 metr os). Tambin investig el porcentaje de pecolos colonizados, riqueza de especie, la equidad, y la i nfluencia de la humedad de pecolo y longitud en la abundancia y la diversidad de escarabajos. Analic a 90 peciolos leosos del suelo y de la vegetacin colgante de cada sitio. Los pecolos fueron disecad os y los escarabajos fueron sacados y fueron identificados como seis diferentes especies de Sco lytinae. Las diferencias en la abundancia y la dive rsidad de escarabajos entre la dos especie entonces fueron comparadas. Este estudio sugiere que no haba diferencia en la diversidad de la especie entre la dos especie de rbol (p > 0.05). Sin embargo, se en contro uan diferencia entre C. polyphlebia y el hbrido. E l fenotipo hbrido posey una abundancia ms alta d e escarabajos. Tambin humedad contenida (ANCOVA, F = 4.93, df = 2, p = 0.0083), la especie de Cecropia (ANCOVA, F= 11.2, df = 1, p = 0.001), y la longitud de pecolo con la especie df de de Cecropia (ANCOVA, F = 5.16, df = 1, p = 0.0244) tuvo una inf luencia en la abundancia de escarabajos. La

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abundancia ms alta de escarabajos en el fenotipo h brido podra indicar las diferencias en la competi cia intraespecfica debido a rasgos fenotpicos de la e specie de Cecropia. Las diferencias en el contenido de la humedad y la longitud de peciolo entre la dos espec ie de Cecropia pueden reflejar la preferencia de pe ciolo y favoritismo por rboles hospederos. Adems, la ab undancia ms alta de escarabajos en la elevacin m s baja podra indicar que la mayora de escarabajos d e corteza no puede ser afectada por el cambio del c lima a diferencia de muchas otra especie de animales y p lantas que son impresionados severamente por las temperaturas crecientes. INTRODUCTION Woody petioles are rarely considered a habitable l ocation for any subcortical-feeding insects, but beetles from the family Scolytinae use several substrates such as xylem, petioles, and the pith of dead twigs as breeding gr ounds (Jordal and Kirkendall 1998). Interestingly enough, several species from the fami ly Scolytinae have a unique ecological relationship with Cecropia trees. These beetles, known colloquially as bark beetles, breed within the fallen, dead, woody petioles that Cecropia trees offer year-round (Jordal and Kirkendall 1998). Therefore, these petioles can provide information about the diversity and abundance of bark beetles found in ty pes of Cecropia Each Cecropia tree can be considered a mini-ecosystem that is col onized by several wood-boring beetles. With high competition, the various genera of bark b eetles demonstrate niche stratification in order to coexis t. Competition can be greater when sharing a petiole (Larimer et al. 2006). So, it is not uncommon to find two or three species of bark beetles in each petiole due to nich e partitioning. For example, Scolytodes aratus panamensis is notorious for having one to four pairs of adult s per petiole (Wood 1983). This is a relatively high number of beetles per petiole. Bark beetles are extremely unique in their breeding and habitat locations. They colonize the leaves around three to fifteen days af ter they have fallen (Wood 1983). Also, their breeding systems can have eight differe nt inbreeding origins (Larimer et al. 2006). Bark beetles breed by having the adult male Scolytine beetle bore an entrance hole through the hard cortex into the soft pith of the p etiole. Then a female bark beetle assumingly joins the male within the petiole by fol lowing a pheromone trail. After meeting, the female begins to burrow in an irregula r pattern and lays one to twenty eggs through the tunnels. The pupae eat away at the pith and escape to find another petiole to inhabit (Wood 1983). The goal of this study is to determine if some spec ies of Scolytine beetles are exclusive to one species of Cecropia It has been hypothesized that bark beetles will n ot be able to easily colonize another species of Cecropia because they are highly specialized and have unique breeding systems. Abundance was pre dicted to be greater in the hybrid species otherwise known as the intermediary phenoty pe due to physiological traits that may favor bark beetles over other species. For inst ance, the Mullerian bodies are less distinct in the hybrid phenotype. This results in a drop of Azteca colonies. However, higher diversity will be found in C. polyphlebia C. polyphlebia is the only species of Cecropia found at high altitudes (Longino 2000). This would lead to a concentration of bark beetles preying upon these Cecropia woody petioles, which can lead to higher diversity due to high competition for similar resou rces. However in the hybrid range, more than one species of Cecropia can coexist, which may lead to lower competition o f resources and thus less diversity (Longino 2000).

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METHODS Two study sites were used in Monteverde, Costa Rica to obtain Cecropia petioles for the research of the Scolytine beetles from July 17, 2008 to August 1, 2008. The high elevation species C. polyphlebia was collected from the Monteverde Cloud Forest (1550m), and the lower elevation hybrid species was collected from the Bajo del Tigre of the Children’s Eternal Rainforest (1400 m). At each site, 30 petioles per tree were collected, thus 90 petioles at each site. Petioles were arbitrarily collected from a variety of locations from the ground to hanging vegetation up to 4 meters high, and a variety of petioles were selected. Petioles were placed in pla stic bags for transport. Petiole moisture and petiole length were determined for each petiole. Petiole moisture was determined using a procedure outlined by Jordal and Kirkendall (1998). They ranked each petiole on a scale of zero to two. Zero was desiccated, one was wet, and two was soft and moist. Petioles were dissected and all the beetles were removed and placed in containers. Beetles were initially p laced in containers filled with ethanol, but classification of color may have been compromis ed with prolonged time in the containers. Containers without ethanol were used af terwards. Scolytine bark beetles were identified by morphospecies. A dissecting microscop e was used to distinguish physical characteristics of color, presence of hair on abdom en, presence of hair on elytra, size, and color. A modified t-test was used to compare diversity. I then calculated abundance, evenness, and species richness for both sites. A tw o-way ANCOVA analysis was performed to see if the type of species, moisture c ontent, or length of petiole influenced the abundance of beetles. RESULTS A total of 180 petioles were dissected from two dif ferent species of Cecropia. 90 petioles were from C. polyphlebia and 90 petioles were of the intermediary phenotype 44% of the petioles were inhabited in the hybrid but only 20% of the petioles were colonized in C. polyphlebia 32% of all the petioles were colonized. A statistically significant difference in abundanc e was found between the two Cecropia species (Table 2). The hybrid species had a total number of 304 beetles, whereas C. polyphlebia had 85 beetles (Table 2). In both species of Cecropia the most abundant beetle species was Morpho 3 and second mos t abundant was Morpho 1 (Table 2). The least abundant beetle species found in C.polyphlebia was either Morpho 5 or 6 (Table 2). The least abundant beetle species found in the hybrid Cecropia was Morpho 2 (Table 2). No significant difference in Shannon-Wei ner diversity index was found between C. polyphlebia (H’ = 1.26) and the hybrid (H’ = 1.23) (Modified t -test, df = 127.9, p > 0.05; Table 2). Six species of beetles w ere found in C. polphlebia and five species in the hybrid (Table 1, Table 2). No signif icant difference in evenness was found. C.polyphlebia had an evenness of 0.76, and the hybrid Cecropia had an evenness of 0.77 (Table 2). S’marg for C.polyphlebia was 1.13, and the hybrid Cecropia S’marg was 19.21 (Table 2). Moisture content was found to increase a s the abundance of beetles increased (ANCOVA, F = 4.93, df = 2, p = 0.008; Figure 3). Al so, the hybrid species had a greater

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abundance of beetles compared to C. polyphlebia (ANCOVA, F = 11.2, df =1, p = 0.001; Figure 2). Furthermore, as the petiole length incre ased within each species of Cecropia the abundance of beetles increased (ANCOVA, F = 5.1 6, df = 1, p = 0.024; Figure 1). Several larvae were observed in many of the occupie d petioles. Furthermore, there were many insects and non-beetle species found in the Mo nteverde Cloud Forest. DISCUSSION Based on results from this study, it was concluded that bark beetles were able to successfully colonize and reproduce in the hybrid s pecies of Cecropia better than in C.polyphlebia This is supported by the fact that there was also a higher abundance of beetles found within the hybrid Cecropia This indicates that there was not a significant difference in diversity, but there was a significant difference in abundance of beetles colonized. Also, 44% of the hybrid petioles were colonized an d 20% of the C.polyphlebia petioles were colonized. One possible explanation f or a higher colonization percentage in the hybrid Cecropia is that the hybrid species offers a better habitat for bark beetles than C.polyphlebia. Through observation, there were significantly less insects other than beetles found in the hybrid petioles than in the C. polyphlebia petioles. This may reduce inter-specific competition between species and allo w for bark beetles to thrive in the hybrid Cecropia Also, the intermediary phenotype may inhibit othe r species that generally colonize Cecropia petioles. For example, hybrid Mullerian bodies, si milar to extrafloral nectaries, are less distinct and are co vered in long hairs. Furthermore, colonies of Azteca that share a mutualistic relationship with Cecropia drop out around the elevation where the hybrid species is found (Longin o 2000). These factors may explain a higher abundance of beetles in the hybrid Cecropia Bark beetles regularly inbreed and generally matur e and mate with their sisters before even leaving the petiole (Beaver et al 2001) In bark beetles, usually one to four pairs of adults was found per petiole (Wood 1983). However the hybrid Cecropia had up to 26 beetles per petiole in this study. Bark beetl e reproductive fitness may be greatly increased in the hybrid phenotypes due to reduced i nter-specific competition (Jordal and Kirkendall 1998). Additionally, bark beetles are co lonizing organisms and regularly inbreed. Therefore, they are not affected by inbre eding depression that may affect their reproductive fitness (Beaver et al. 2001). Even though there was a difference in abundance be tween the hybrid and C. polyphlebia there was not a significant difference in diversi ty. Most beetle species may be able to colonize both of the Cecropia species, but beetles may be able more successful in the hybrid species of Cecropia This would lead to higher abundance of beetles in the hybrid Cecropia Also, altitude may play a role in affecting abund ance of bark beetles but may not prohibit species from traveling to differen t altitudes. Studies done by Wilkinson (2002) and Strauss (2007) both found that all speci es were found at both of the sites separated by altitude. Further studies should be co mpleted to specifically observe the altitudinal effects on bark beetles. Interestingly enough, Morphospecies 6 was found on ly in the Monteverde Cloud Forest. Although this is contradictory to previous studies, this may be due to a variation in sample sizes and the time in which the study too k place. Furthermore, a high number

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of petioles studied were filled with larvae, and th ere were many more beetles per petiole. Collection of petioles may have occurred during a c ommunity turnover time, where many bark beetles were emerging for their migratory phas e to locate new hosts for breeding material (Berryman 1983). In addition, differences in the species of Cecropia with varying petiole lengths affected the abundance of bark beetles. Therefore, bark beetles may prefer specific habitats and petiole lengths. Overall, as petiole length increased in each species of Cecropia the abundance of beetles increased as well. Large r petioles would have less intense competition for similar resources. Also spa tial partitioning would be more successful in longer petioles. Jordal and Kirkendal l (1998) found that many bark beetles were found in a specific tissue of the Cecropia petioles. For instance, S.maurus colonized the base of the petiole, but S. acares and S. cecropiavorus colonized the fibrous tissue. With longer petioles, there are more resources to s hare thus allowing a greater abundance of beetles to be supported. As petiole moisture increases, abundance of beetle s increases. Bark beetles may prefer petioles that are in the shade and moist. Th erefore, bark beetles favor certain tree sites. This coincides with the study done by Jordal and Kirkendall (1998). They found moist petioles in shaded forest sites had ten or mo re egg tunnels per petiole in comparison to dry, sun exposed sites, which were ch aracterized by Hypothenemus species. In this study, there were several petioles that we re not colonized at all. Only 32% of the petioles studied were colonized. In the stud y done by Jordal and Kirkendall (1998) 83% of their petioles were colonized. The differenc e in colonization may be counterbalanced by the high amount of bark beetles found per petiole. Bark beetles complete their whole life cycle protected within th e petiole (Rudinsky 1962). However, they may leave to search for a new host or reproduc e. My results may indicate that collection of data may have been during an inbreedi ng season, where many are drawn to petioles to reproduce. This can explain why there were many beetles per pe tiole and why few were colonized. With the high abundance of bark beetles found in l ower elevations, climate change may not be a factor that affects bark beetle s. However, Scolytinae beetles prefer moist petioles, which means they may have a harder time finding petioles that are not desiccated in the future. However, there was one s pecies found in the higher elevations that was not found in the lower elevations (Morpho 6). This specific species of bark beetle may suffer from climate change if this speci es is only found in higher elevations. Further investigation may want to study the effects of climate change on bark beetles. For example, the ever-increasing dry days in Monteverde may have significant effects on bark beetle habitats. As the Earth warms and continues to alter the face of our landscape, it is essential to see the impacts climate change will have on biod iversity. Biodiversity is threatened as global warming changes the very basics of our ecosy stems. The carbon-enriched atmosphere has wounded species and ecosystems for m illions of years. As biodiversity is rapidly declining due to climate change and anthrop ogenic factors, this study shows that bark beetles may not be affected by climate change and may even benefit. ACKNOWLEDGEMENTS

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I would like to thank Tania Chavarrio Pizarro for a dvising me throughout this entire research project. I would also like to thank Karen Masters for helping and supporting me throughout the planning process a s well as with any follow-up questions I ever had. I would like to thank Pablo and Moncho for helping m e with any questions or supplies I needed. I really w ant to thank Nathan Spaht and Caitlin Loooby for he lping me collect data and keeping my sanity. Finally, I w ant to thank every person on the Summer 2008 progra m, my trip and life will not be the same without you! LITERATURE CITED Beaver, R.A., B.H. Jordal and L.R. Kirkendall. 2001 Breaking taboos in the tropics: incest promotes colonization by wood-boring beetles. Global Ecology and Biogeography 10(4): 345-357. Berryman, A.A. and K.F. Raffa. 1983. The Role of Pl ant Resistance in the Colonization Behavior and Ecology of Bark Beetles (Coleoptera: Scolytidae). 5 3:27-49. Jordal, B.H. and L.R. Kirkendall. 1998. Ecological relationships of a guild of tropical beetles in Cecropia petioles in Costa Rica. Journal of Tropical Ecology 14(2): 153-176 Larimer, A., A. Moe, M. Moyano and R. Oono. 2006. “ Distribution and dispersal of two bark beetle species in Cecropia petioles.” Organizacin para Estudios Tropicales. Course Book. Longino, J.T. 2000. Myrmecophytes. pp. 293. In: Monteverde: Ecology and Conservation of a Tropical Cloud Forest Nadkarni, N.M. and Wheelwright, N.T. (Ed.). Oxfor d Univeristy Press: Oxford, New York. Rudinsky, J.A. 1962. Ecology of Scolytidae. Annual Review of Entymology. 27:327-348. Strauss, A. 2007. Differences in bark beetle (Coleo ptera: Curculionidae) community composition within Cecropia obtusifolia (Cecropiaceae) petioles in two habitats in Monteve rde, Costa Rica. CIEE Tropical Ecology and Conservation, Fall 2007: 77-86 Vitug, S. 2005. Scolytinae within Cecropia petioles. UCEAP-IMV Tropical Biology and Conservation Fall 2005:1-9. Wilkinson, K. 2002. Distribution and Niche Partitio ning of Beetles from Two Cecropia spp. (Cecropiacea e) in Monteverde, Costa Rica. CIEE Tropical Ecology and Conservation, Fall 2002: 60-7 0. Wood, S.L. 1983. Scolytodes atratus panamensis (Escarabajit de Guaramo, Cecropia petiole Borer). pp. 768-769. In: Costa Rican Natural History D.H. Janzen (Ed.). University of Chicago Press: Chicago, Illinois. Table 1. The abundance of each morphospecies found in C. polyphlebia and the hybrid Species C .polyphlebia Hybrid

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Morpho 1 25 106 Morpho 2 6 13 Morpho 3 40 142 Morpho 4 8 19 Morpho 5 3 24 Morpho 6 3 0 Table 2. The abundance (N), evenness (E), Shannon-W einer Index (H’), Species Richness (S), and S’marg (S’marg) between C. polyphlebia and the hybrid (Modified ttest, df=127.85 p=0.1-0.2). C. polyphlebia Hybrid E 0.76 0.77 N 85.00 304.00 S 6.00 5.00 H' 1.36 1.23 S'marg 1.13 19.21 Table 3. Degrees of Freedom, F Ratio, and Probabili ty > F for Species of Cecropia Moisture content, and Species of Cecropia and Length using 2-way ANCOVA test. Source DF F Ratio Prob > F Species 1 11.2419 0.001 Moisture 2 4.9336 0.0083 Species and Length 1 5.1569 0.0244 n n

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Figure 1. Petiole length (mm) in C. polyphlebia (blue) and hybrid (red) in relation to the abundance of beetles (ANCOVA, F = 5.16, df = 1, p = 0.0244) n r r Figure 2. The abundance of beetles in C. polyphlebia and the hybrid Cecropia (ANCOVA, F = 11.2, df = 1, p = 0.001)

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n r Figure 3. The abundance of beetles versus moisture content in Cecropia (ANCOVA, F = 4.93, df = 2, p = 0.0083)


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Patrones de abundancia del pecolo y diversidad de los escarabajos de corteza (Scolytinae) de los rboles de Cecropia en Monteverde, Costa Rica
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Patterns of petiole abundance and diversity in bark beetles (Scolytinae) of Cecropia trees in Monteverde, Costa Rica
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Cecropia trees regularly shed their woody, large petioles year round. This provides bark beetles from the
family Scolytinae with a dependable and stable microhabitat. Bark beetles bore into the petioles, lay their
eggs, and feed on the pith (Wood 1983). This study was conducted in Monteverde, Costa Rica. It examined
the abundance and diversity of bark beetles between Cecropia polyphlebia in the Monteverde Cloud Forest
(1550 meters) and an intermediary phenotype at Bajo del Tigre (1400 meters). It also investigated the
percent of petioles colonized, species richness, evenness, and the influence of petiole moisture and length
on the abundance and diversity of beetles. I analyzed 90 dead, woody petioles from the ground and from
hanging vegetation from each site. Petioles were dissected and beetles were removed and identified by one
of six Scolytinae morphospecies. Differences in the abundance and diversity of beetles between the two
species were then compared. This study suggests that there was no difference in species diversity between
the two tree species (p > 0.05). However, a difference in abundance between the hybrid phenotype and C.
polyphlebia was observed. The hybrid phenotype possessed a higher abundance of beetles. Also moisture
content (ANCOVA, F = 4.93, df = 2, p = 0.0083), the species of Cecropia (ANCOVA, F = 11.2, df = 1, p
=0.001), and petiole length with Cecropia species (ANCOVA, F = 5.16, df = 1, p = 0.0244) had an
influence on the abundance of beetles. The higher abundance of beetles in the hybrid phenotype could
indicate differences in interspecific competition due to phenotypic traits of the Cecropia species.
Differences in moisture content and petiole length between the two Cecropia species may reflect petiole
preference and favorability of tree hosts. Furthermore, the higher abundance of beetles in the lower
elevation hybrid phenotype could indicate that the majority of bark beetles may not be affected by climate
change unlike many other species of animals and plants that are being severely impacted by the increasing
temperatures.
Este estudio se realiz en Monteverde, Costa Rica. Examin la abundancia y la diversidad de los escarabajos de corteza entre Cecropia polyphlebia (1550 metros) en el Bosque Nuboso de Monteverde y un fenotipo intermedio en el Bajo del Tigre (1400 metros). Tambin investig el porcentaje de pecolos colonizados, riqueza de especies, igualdad y la influencia de la humedad del pecolo y la longitud de la abundancia y diversidad de escarabajos.
546
Text in English.
650
Bark beetles--Behavior--Costa Rica--Monteverde Cloud Forest Reserve
Interspecific interactions--Cecropia
4
Escarabajos de corteza--Comportamiento--Costa Rica--Reserva Bosque Nuboso Monteverde
Interacciones interspecficas--Cecropia
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Tropical Ecology 2008
Interspecific competition--Cecropia
Bark beetle feeding preferences
Ecologa Tropical 2008
Preferencias alimenticias del escarabajo de corteza
Competencia interspecfica--Cecropia
655
Reports
720
CIEE
773
t Monteverde Institute : Tropical Ecology
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