| two species of acuaria bremser, 1811 (nematoda: acuarioidea: acuariidae) in passerine birds from the area de conservacion guanacaste, costa rica. | two species of acuaria were collected from passerine birds from the area de conservacion guanacaste, costa rica. acuaria mayori lent, freitas and proenca, 1945, was collected from myiarchus nuttingi. specimens from costa rica differ from the original description by having a spicule ratio of 1:1.5-1.7 versus 1:1.43-1.47, as well as shorter spicules and female tails. acuaria wangi n. sp. in hylophylax naevioides and gymnopithys leucaspis resembles a. alii, a. crami, a. cyanocitta, a. minuta, a. pa ... | 2003 | 14627153 |
| species loss, delayed numerical responses, and functional compensation in an antbird guild. | when a community loses species through fragmentation, its total food consumption may drop. compensatory responses of remaining species, whereby survivors assume roles of extinct competitors, may reduce the impact of species loss through numerical or functional responses. we measured compensatory responses in two remaining antbird species on barro colorado island, panama, four decades after the loss of their dominant competitor, the ocellated antbird, phaenostictus mcleannani. we compared current ... | 2011 | 21661573 |
| ecological opportunity leads to the emergence of an alternative behavioural phenotype in a tropical bird. | loss of a dominant competitor can open ecological opportunities. ecological opportunities are considered prerequisites for adaptive radiations. nonetheless, initiation of diversification in response to ecological opportunity is seldom observed, so we know little about the stages by which behavioural variation either increases or coalesces into distinct phenotypes. here, a natural experiment showed that in a tropical island's guild of army ant-following birds, a new behavioural phenotype emerged ... | 2015 | 25640464 |
| captive rearing experiments confirm song development without learning in a tracheophone suboscine bird. | the origin of vocal learning in animals has long been the subject of debate, but progress has been limited by uncertainty regarding the distribution of learning mechanisms across the tree of life, even for model systems such as birdsong. in particular, the importance of learning is well known in oscine songbirds, but disputed in suboscines. members of this diverse group (∼1150 species) are generally assumed not to learn their songs, but empirical evidence is scarce, with previous studies restric ... | 2014 | 24788343 |
| low metabolism and inactive lifestyle of a tropical rain forest bird investigated via heart-rate telemetry. | birds in the lowland tropical rain forest are expected to have low energy turnover. here, we used heart rate telemetry to estimate nighttime resting metabolic rate (rmr), daily energy expenditure (dee), and locomotor activity of a small, long-lived tropical rain forest-understory bird, the spotted antbird (hylophylax naevioides). heart rate was linearly related to oxygen consumption in respirometry measurements that encompassed 96% of heart rates measured in wild birds. heart rates in the wild r ... | 2009 | 19656073 |