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Devries P.,University of New Orleans | Walla T.,Mesa State College | Greeney H.,Yanayacu Biological Station and Center for Creative Studies | Chao A.,National Tsing Hua University | Ricotta C.,University of Rome La Sapienza
Diversity and Distributions | Year: 2010

Aim Differentiation of sites or communities is often measured by partitioning regional or gamma diversity into additive or multiplicative alpha and beta components. The beta component and the ratio of within-group to total diversity (alpha/gamma) are then used to infer the compositional differentiation or similarity of the sites. There is debate about the appropriate measures and partitioning formulas for this purpose. We test the main partitioning methods, using empirical and simulated data, to see if some of these methods lead to false conclusions, and we show how to resolve the problems that we uncover. Location South America, Ecuador, Orellana province, Rio Shiripuno. Methods We construct sets of real and simulated tropical butterfly communities that can be unambiguously ranked according to their degree of differentiation. We then test whether beta and similarity measures from the different partitioning approaches rank these datasets correctly. Results The ratio of within-group diversity to total diversity does not reflect compositional similarity, when the Gini-Simpson index or Shannon entropy are used to measure diversity. Additive beta diversity based on the Gini-Simpson index does not reflect the degree of differentiation between N sites or communities. Main conclusions The ratio of within-group to total diversity (alpha/gamma) should not be used to measure the compositional similarity of groups, if diversity is equated with Shannon entropy or the Gini-Simpson index. Conversion of these measures to effective number of species solves these problems. Additive Gini-Simpson beta diversity does not directly reflect the differentiation of N samples or communities. However, when properly transformed onto the unit interval so as to remove the dependence on alpha and N, additive and multiplicative beta measures yield identical normalized measures of relative similarity and differentiation. © 2009 Blackwell Publishing Ltd.


The Brown Nunlet (N. brunnea) is one of six species of small puffbirds in the genus Nonnula. Here, we describe a nest of Brown Nunlet from Amazonian Ecuador. The nests' architecture diverges from that of other bucconids, built neither in a subterranean burrow nor in a termitarium, but rather is a flattened, dome-shaped structure composed of leaf litter above a shallow depression. Structural integrity of the leafy dome is created with carefully placed sticks and the inner chamber is entered through a short tunnel. We also provide observations that clarify uncertainties in nest placement of White-chested Puffbird (Malacoptila fusca) and observations on the breeding of other Bucconidae in Amazonian Ecuador.


Dyer L.A.,University of Nevada, Reno | Walla T.R.,Mesa State College | Greeney H.F.,University of Nevada, Reno | Greeney H.F.,Yanayacu Biological Station and Center for Creative Studies | And 2 more authors.
Biotropica | Year: 2010

Multitrophic interactions play key roles in the origin and maintenance of species diversity, and the study of these interactions has contributed to important theoretical advances in ecology and evolutionary biology. Nevertheless, most biodiversity inventories focus on static species lists, and prominent theories of diversity still ignore trophic interactions. The lack of a simple interaction metric that is analogous to species richness is one reason why diversity of interactions is not examined as a response or predictor variable in diversity studies. Using plant-herbivore-enemy trophic chains as an example, we develop a simple metric of diversity in which richness, diversity indices (e.g., Simpson's 1/D), and rarefaction diversity are calculated with links as the basic unit rather than species. Interactions include all two-link (herbivore-plant and enemy-herbivore) and three-link (enemy-herbivore-plant) chains found in a study unit. This metric is different from other indices, such as traditional diversity measures, connectivity and interaction diversity in food-web studies, and the diversity of interaction index in behavioral studies, and it is easier to compute. Using this approach to studying diversity provides novel insight into debates about neutrality and correlations between diversity, stability, productivity, and ecosystem services. © 2010 The Author(s). Journal compilation © 2010 by The Association for Tropical Biology and Conservation.


Greeney H.F.,Yanayacu Biological Station and Center for Creative Studies | Greeney H.F.,University of Nevada, Reno | Juina M.E.J.,Yanayacu Biological Station and Center for Creative Studies
Wilson Journal of Ornithology | Year: 2010

The Jocotoco Antpitta (Grallaria ridgelyi) is an endangered and poorly studied inhabitant of montane bamboo (Chusquea spp.) thickets of extreme southeastern Ecuador. There is nothing known of the breeding biology of Jocotoco Antpitta apart from a single record of a dependent juvenile, and we describe a nest of this species for the first time. The nest was a bulky cup composed primarily of dead plant materials and firmly supported by a large clump of epiphytes on the side of a dead trunk. The single nestling was provisioned at a rate of 1.96 feedings/hr during the final 5 days prior to fledging. Two adults brought food to the nestling, often delivering prey from a nearby worm-feeding station created by the Jocotoco Foundation. The pair we studied may breed twice a year, but this may have been facilitated by their proximity to the artificial feeder. © 2010 by the Wilson Ornithological Society.


Heming N.M.,University of Brasilia | Greeney H.F.,Yanayacu Biological Station and Center for Creative Studies | Marini M.A.,University of Brasilia
Natureza a Conservacao | Year: 2013

Life-history strategies of Neotropical birds differ markedly from their Nearctic counterparts, yet the lack of detailed information on most Neotropical species hinders meaningful comparisons. We performed a gap analysis with several basic life-history traits of New World flycatchers of the subfamily Fluvicolinae. We found breeding data - mostly on clutch sizes and linear egg measurements - in 303 publications spanning the years 1838 to 2012. Data from the USA and Argentina were more abundant, with the number of publications per country being significantly and positively related to human development index (HDI) and Fluvicolinae breeding species richness. The amount of available clutch size information for each species was positively related to species' range size and relative abundance. More research is needed concerning narrowly distributed and uncommon species. Additional efforts to gather data on all Neotropical species are, however, crucial for future advancements. © 2013 ABECO.


Zyskowski K.,Yale University | Greeney H.F.,Yanayacu Biological Station and Center for Creative Studies
Condor | Year: 2010

Thripadectes treehunters are among the most poorly known cavity-nesting furnariids. In this paper we review the existing information on their nests, present new field observations from ecuador, and add unpublished museum data. We describe for the first time the nests of two species, T. flammulatus and T. holostictus. Nests of Thripadectes are all shallow cups of vegetative material, lacking any lining of animal origin such as feathers or hair. Most species have consistent preferences for particular plant materials. Thripadectes rufobrunneus, T. virgaticeps, and T. holostictus use mainly rootlets, T. melanorhynchus uses stems of compound leaves exclusively, and T. flammulatus incorporates plant materials derived from grass, bamboo, and treeferns. Larger samples of nests from across these species' ranges are needed to determine the generality of this pattern and whether the availability of material plays a role. Several features of Thripadectes nest architecture are shared by putative sister genera Automolus, Hylocryptus, and Hyloctistes. © The Cooper Ornithological Society 2010.


Greeney H.F.,Yanayacu Biological Station and Center for Creative Studies | Dyrcz A.,Wrocław University
Ornitologia Colombiana | Year: 2011

We made observations on the reproductive habits of Pale-edged Flycatcher (Myiarchus cephalotes) nesting in nest boxes and under the eaves of human dwellings in northeastern Ecuador. We found a total of six nests, likely built by the same two pairs. Nest construction lasted around 23 days at one nest and was performed only by the female. Most clutches are initiated during the drier months, but there may be some breeding year-round. Clutch size ranged from two to three eggs. Only females incubated and spent the night on the nest. Patterns of attendance during incubation were fairly regular and eggs were covered for 62% of daylight hours. Incubation period was 18 days at two nests. At two nests eggs hatched synchronously and at a third two eggs hatched 24 h prior to the final egg. The nestling period was 18 days. Based on observations of one banded pair in 2008 and 2009, females provide the majority of nestling care (61%). Nestlings were provisioned with a large percentage of adult Lepidoptera and cicadas, with females bringing predominantly Lepidoptera and males favoring cicadas. After leaving the nest, young birds remained with their parents for at least 10 weeks and were still provisioned by them for at least the first nine weeks.


Greeney H.F.,Yanayacu Biological Station and Center for Creative Studies
Ornitologia Colombiana | Year: 2013

The Ash-breasted Tit-Tyrant (Anairetes alpinus) is a range-restricted flycatcher (Tyrannidae) inhabiting the high Andes of Peru, Bolivia, and Argentina. I provide the first description of nest architecture for this species based on a nest encountered in southern Peru. The nest was a deep, compact cup of moss, thickly but loosely lined with feathers and built 1.4 m above the ground in a hanging epiphyte clump. It was similar in architecture and means of support to the nests of other Anairetes, all of which also share an internal lining of feathers.


Greeney H.F.,Yanayacu Biological Station and Center for Creative Studies | Walla T.R.,Mesa State College | Lynch R.L.,Yanayacu Biological Station and Center for Creative Studies
Zoologia | Year: 2010

Insect-food-plant associations have been shown to be influenced by the chemical, physical and nutritional characteristics of plants. We suggest that among insect larvae that use leaf material to build shelters, food-plant use may be constrained by differences in host leaf structure, illuminating a rarely investigated aspect of insect-plant interactions. To explore the potential effects of leaf structure on shelter building behavior in a Neotropical skipper butterfly, we investigated shelter building patterns on two congeneric food-plants that varied in leaf thickness. Shelter architecture varied significantly between hosts, with thicker leaves requiring longer cuts to construct shelters. The relationship between shelter building behavior and leaf structure is discussed in relation to selection pressures on larval shelters and food-plant choice. © 2010 Sociedade Brasileira de Zoologia.


Greeney H.F.,Yanayacu Biological Station and Center for Creative Studies | Gelis R.A.,Pluma
Ornitologia Colombiana | Year: 2011

The Pearled Treerunner (Margarornis squamiger) is a small ovenbird (Furnariidae) inhabiting the upper strata of Neotropical montane forests. Little is known of its breeding habits despite its wide distribution and abundance within appropriate habitat. The genus Margarornis is considered closely related to Premnoplex barbtails, but details of nest architecture supporting this relationship are unavailable. Here we provide the first detailed description of nest architecture for the Pearled Treerunner from a nest encountered in northwest Ecuador. The nest was a tightly woven ball of moss and rootlets, similar in shape to that of the Spotted Barbtail (Premnoplex brunnescens) and presumably built in a similar manner. Nest architecture and nestling behavior support a close relationship between Margarornis and Premnoplex.

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