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Certain traits, including those that make species more vulnerable to consumption by predators, may make species inherently susceptible to population declines and local species loss (i.e. extirpation). To examine whether small mammal and arthropod granivory is a mechanism of community change via association with extirpation events, we studied seed predation on six phylogenetically paired extirpated and extant species from Kalamazoo, Michigan, using a seed removal experiment in a restored prairie. We also examined differences in granivore preferences for seed traits (seed mass, water content, C:N content) and differences in seed traits between extirpated and extant taxa. Granivory was independent of extirpation status but was affected by seed traits. Small mammals consumed more seeds than arthropods and preferentially consumed large seeds, while arthropods consumed small seeds and those with higher C:N ratios (lower nitrogen content). Extirpated and extant taxa did not differ in seed traits, perhaps explaining why they did not differ in granivory. Granivory was phylogenetically conserved, suggesting that certain plant families are more susceptible to granivores than others. This study indicates that granivory varies across species and seed traits in a prairie restoration, but does not likely influence extirpation in this system. Understanding granivore preferences may help managers predict establishment success for rare or extirpated species with particular traits being introduced into prairie restorations.

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The alpaca (Vicugna pacos) is a ruminant livestock species in the South American camelid family. There are more than 9 million South American camelids globally that make important contributions to the livelihoods of rural farmers through conversion of low quality roughages to high quality food and fibre. Reproductive biotechnologies for alpacas are not well developed compared with those for other ruminant livestock species. In particular, embryo cryopreservation technologies are lacking. The objective of this study was to evaluate under field conditions a vitrification protocol originally developed for old world camels that we adapted for use in alpacas. Potential donors were evaluated for follicular development using a 7.5-MHz ultrasound probe. Hembras (sexually mature female alpacas) with ovarian follicles 7-10mm in diameter were behaviour tested to determine sexual receptivity, and receptive females were naturally mated to a proven herd sire. At the time of breeding, non-superovulated donors (n=4) received 30μg gonadorelin. Embryos were nonsurgically collected 7 days after breeding and handled at 20°C. Diameter of harvested embryos (n=4 quality grade 1 hatched expanded blastocysts) was measured using an eyepiece reticle. All recovered embryos were placed individually into 0.5-mL drops of vitrification solution (VS1: 1.4M glycerol) for 5min, 0.5-mL drops of VS2 (1.4 M glycerol + 3.6M ethylene glycol) for 5min, 0.05-mL drops of VS3 (3.4 M glycerol + 4.6M ethylene glycol) for 20s, and 0.05-mL drops of VS3 for 20s while loading into open-pulled straws (OPS). Each OPS was plunged directly into liquid nitrogen for storage for 29 days. At warming, each OPS was submerged into a 1-mL drop of warming solution 1 (WS1: 0.5M galactose) for 1min followed by 1min in WS2 (0.25 M galactose) for 5min before being incubated at 37°C in 5% CO2 in humidified air for 21h in 1mL of Syngro holding medium supplemented with 10% (vol/vol) alpaca serum. Embryos that grew during culture (n=2) were transferred individually into synchronous recipients, and embryos that did not appear to grow (n=2) were transferred together as a pair. Prior to embryo transfer, potential recipients were evaluated ultrasonographically as described previously. Hembras with ovarian follicles 7-10mm in diameter were behaviour tested, and sexually receptive females received 30μg gonadorelin 6 days before embryo transfer. Final selection of recipients (n=3) was based on presence of a corpus luteum and nonreceptive behaviour to a herd sire 24h before transfer. Pregnancy was detected ultrasonographically, and fetal heartbeat was detected 29 days post-transfer in one of the three recipients. Ultrasound at 177 days post-transfer revealed that the pregnancy, generated from a 400μm×375μm vitrified-warmed embryo that had grown in culture, was still ongoing. If this pregnancy results in the birth of a live cria (newborn alpaca), it would represent-to the best of our knowledge-the world's first cria born from a cryopreserved alpaca pre-implantation embryo. It would also demonstrate the potential utility of this protocol under field conditions.

As the field of ecology evolves, analyses synthesizing trends in key topics addressed over the decades can provide historical context for the development of novel theories and methods, identify “hot topics” over time, and guide future research directions. Such syntheses in a field that aims to diversify can also help quantify efforts to increase representation and authorship by underrepresented groups in STEM. To identify hot topics in ecology, we analyzed key themes in the top‐cited ecology papers in three two‐decade timeframes spanning 1960–2019. We also analyzed authorship trends (gender identity and nationality) in the top‐cited papers. We documented a shift from descriptive studies in single biological systems in the 1960–1970, to more synthesis‐based papers and studies discussing human impacts on the environment in the 1980–1990, while the 2000s were dominated by novel quantitative and macroecological approaches. The top‐cited papers were overwhelmingly from the United States and Europe, highlighting the need to make studies from across the globe more visible and accessible in the ecological literature. Finally, we detected a trend for more papers led by women authors, but a decline in papers with women last authors, indicating a need to retain women in leadership positions. Overall, our hot topics analysis highlights the expanding breadth and quantitative nature of ecology, but illustrates barriers to diversity in the perspectives represented in the top‐cited papers.