Impacts of fire and prospects for recovery in a tropical peat forest ecosystem.

Uncontrolled fires place considerable burdens on forest ecosystems, compromising our ability to meet conservation and restoration goals. A poor understanding of the impacts of fire on ecosystems and their biodiversity exacerbates this challenge, particularly in tropical regions where few studies have applied consistent analytical techniques to examine a broad range of ecological impacts over multiyear time frames. We compiled 16 y of data on ecosystem properties (17 variables) and biodiversity (21 variables) from a tropical peatland in Indonesia to assess fire impacts and infer the potential for recovery. Burned forest experienced altered structural and microclimatic conditions, resulting in a proliferation of nonforest vegetation and erosion of forest ecosystem properties and biodiversity. Compared to unburned forest, habitat structure, tree density, and canopy cover deteriorated by 58 to 98%, while declines in species diversity and abundance were most pronounced for trees, damselflies, and butterflies, particularly for forest specialist species. Tracking ecosystem property and biodiversity datasets over time revealed most to be sensitive to recurrent high-intensity fires within the wider landscape. These megafires immediately compromised water quality and tree reproductive phenology, crashing commercially valuable fish populations within 3 mo and driving a gradual decline in threatened vertebrates over 9 mo. Burned forest remained structurally compromised long after a burn event, but vegetation showed some signs of recovery over a 12-y period. Our findings demonstrate that, if left uncontrolled, fire may be a pervasive threat to the ecological functioning of tropical forests, underscoring the importance of fire prevention and long-term restoration efforts, as exemplified in Indonesia.

Anti-bat ultrasound production in moths is globally and phylogenetically widespread.

Warning signals are well known in the visual system, but rare in other modalities. Some moths produce ultrasonic sounds to warn bats of noxious taste or to mimic unpalatable models. Here, we report results from a long-term study across the globe, assaying moth response to playback of bat echolocation. We tested 252 genera, spanning most families of large-bodied moths, and document anti-bat ultrasound production in 52 genera, with eight subfamily origins described. Based on acoustic analysis of ultrasonic emissions and palatability experiments with bats, it seems that acoustic warning and mimicry are the raison d'être for sound production in most moths. However, some moths use high-duty-cycle ultrasound capable of jamming bat sonar. In fact, we find preliminary evidence of independent origins of sonar jamming in at least six subfamilies. Palatability data indicate that jamming and warning are not mutually exclusive strategies. To explore the possible organization of anti-bat warning sounds into acoustic mimicry rings, we intensively studied a community of moths in Ecuador and, using machine-learning approaches, found five distinct acoustic clusters. While these data represent an early understanding of acoustic aposematism and mimicry across this megadiverse insect order, it is likely that ultrasonically signaling moths comprise one of the largest mimicry complexes on earth.

Pollination ecology of the ghost orchid (Dendrophylax lindenii): A first description with new hypotheses for Darwin's orchids.

The structural variation of orchids enables myriad fascinating symbiotic relationships with organisms across kingdoms. Orchids are frequently known for having elaborate arms races with their pollinators that result in intricate morphologies in both parties, and flowers with long corollas hypothesized to be pollinated only by individual species of long tongued hawkmoths are of particular concern for conservation. Florida's endangered ghost orchid, Dendrophylax lindenii, has long been confidently assumed to be pollinated by one species (Cocytius antaeus), despite the presence of a resident community of multiple suitable long-tongued candidates. Here we present the first description of ghost orchid pollination, and describe novel remote camera trapping methods. Pollination of D. lindenii by Pachylia ficus disproves long-standing hypotheses concerning the pollination ecology of long-spurred orchids, and new multiple pollinator hypotheses are proposed. We discuss the broader implications for the conservation of an endangered species, orchids globally, and the importance of Everglades restoration.