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Ítem A ‘slow pace of life’ in Australian old-endemic passerine birds is not accompanied by low basal metabolic rates(Springer Verlag, 2016-05-01) Buttemer, William A.Life history theory suggests that species experiencing high extrinsic mortality rates allocate more resources toward reproduction relative to self-maintenance and reach maturity earlier (‘fast pace of life’) than those having greater life expectancy and reproducing at a lower rate (‘slow pace of life’). Among birds, many studies have shown that tropical species have a slower pace of life than temperate-breeding species. The pace of life has been hypothesized to affect metabolism and, as predicted, tropical birds have lower basal metabolic rates (BMR) than temperate-breeding birds. However, many temperate-breeding Australian passerines belong to lineages that evolved in Australia and share ‘slow’ life-history traits that are typical of tropical birds. We obtained BMR from 30 of these ‘old-endemics’ and ten sympatric species of more recently arrived passerine lineages (derived from Afro-Asian origins or introduced by Europeans) with ‘faster’ life histories. The BMR of ‘slow’ temperate-breeding old-endemics was indistinguishable from that of new-arrivals and was not lower than the BMR of ‘fast’ temperate-breeding non-Australian passerines. Old-endemics had substantially smaller clutches and longer maximal life spans in the wild than new arrivals, but neither clutch size nor maximum life span was correlated with BMR. Our results suggest that low BMR in tropical birds is not functionally linked to their ‘slow pace of life’ and instead may be a consequence of differences in annual thermal conditions experienced by tropical versus temperate species. © 2016, Springer-Verlag Berlin Heidelberg.Ítem Nesting behavior of male and female Undulated Antshrikes (Frederickena unduliger)(Association of Field Ornithologists, 2016-03-01) Londoño Guerrero, Gustavo AdolfoUndulated Antshrikes (Frederickena unduliger) inhabit dense lowland humid forest understory and, as with other species of antbirds, many aspects of their behavior and ecology are poorly known, especially their breeding biology. We provide the first detailed information about their breeding biology based on three nests monitored in the buffer zone of the Manu National Park, Madre de Dios, Peru, from August to December in 2012 and 2013. Nests (N = 3) were large cups woven to the crossing of two horizontal branches. Eggs were white with purplish hairlines and spots, and all three clutches consisted of two eggs. Both males and females incubated eggs and fed nestlings, but only females incubated eggs at night.Ítem Nesting biology of the Lanceolated Monklet (Micromonacha lanceolata) in southeastern Peru(Wilson Ornithological SOC, 2016-09-01) Londoño Guerrero, Gustavo AdolfoThe Lanceolated Monklet (Micromonacha lanceolata) is a puffbird (Bucconidae) generally considered rare throughout its range. This species is little-studied and its reproductive behavior is largely unknown. Here, we provide the first detailed account of its nesting biology. All 17 nests consisted of round tunnels in earthen banks terminating in widened brood chambers. Tunnels averaged 405.41 +/- 59.52 mm in length (n = 14) and 68.64 +/- 13.12 by 57.89 +/- 12.20 mm (n = 16) in diameter at the entrances. The clutch size was two. The unmarked, white eggs averaged 22.53 +/- 1.04 by 18.29 +/- 0.71 mm (n = 22) and weighed 3.84 +/- 0.39 g (n = 19). The incubation period, determined from one nest was 25 days. The number of trips made from three nests averaged 3.42 +/- 1.12 per day (n = 33), with each absence lasting an average of 70.54 +/- 89.98 mins (n = 113). Nest attentiveness steadily increased from 11.55 to 71.73% and on-bouts from these three nests averaged 166.28 +/- 96.58 mins (n = 79). During the nestling period, which we determined from one nest to span 22-23 days, food deliveries consisted of large insects and larvae; averaged over four nests, attendants made 1.72 +/- 0.78 (n = 28 days) deliveries per hour.