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Figure 3 in Husbandry, captive breeding, larval development and stages of the Malayan horned frog Megophrys nasuta (Schlegel, 1858) (Amphibia: Anura: Megophryidae)

Figure 3. Megophrys nasuta larvae in stages 18 to 22. Drawings: R. Bach.

Figure 7 in Husbandry, captive breeding, larval development and stages of the Malayan horned frog Megophrys nasuta (Schlegel, 1858) (Amphibia: Anura: Megophryidae)

Figure 7. Megophrys nasuta larvae in stages 30 to 34. Photos: M. Wildenhues.

Figure 6 in Husbandry, captive breeding, larval development and stages of the Malayan horned frog Megophrys nasuta (Schlegel, 1858) (Amphibia: Anura: Megophryidae)

Figure 6. Megophrys nasuta larvae in stages 25 to 29. Photos: M. Wildenhues.

Figure 9 in Husbandry, captive breeding, larval development and stages of the Malayan horned frog Megophrys nasuta (Schlegel, 1858) (Amphibia: Anura: Megophryidae)

Figure 9. Megophrys nasuta larvae in stages 41 to 46. Photos: M. Wildenhues.

opencc-zeroApr 2023View details →

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Data for: The relationships of breeding stage to daytime singing behaviour and song perch height in Bermuda White-eyed Vireos (Vireo griseus bermudianus)

Bird song is crucial for attracting mates and defending territories, but different types of song or different singing behaviours may be involved in acquiring or maintaining each resource. Furthermore, male songbirds may adjust when and where they sing throughout the breeding season, depending on their breeding stage. However, such relationships remain untested in several avian taxa. Here, we studied male Bermuda White-eyed Vireos (Vireo griseus bermudianus), a passerine with two distinct song types (discrete and rambling), to test the mate attraction and territory defence hypotheses. We compare song production and song perch height among different stages of the breeding season and during the non-breeding season. We show that male vireos produce both song types during the breeding and non-breeding seasons, suggesting dual roles in mate choice and territorial defence. Song production did not differ significantly between the breeding and non-breeding seasons, but, within the breeding season, males without nesting duties sang significantly more songs than males with nesting duties. Song perch height was higher during the breeding season versus non-breeding season, among males without nesting duties compared to males with nesting duties, and when males produced discrete versus rambling songs. Our findings suggest that male vireos increase their conspicuousness to prospecting females by increasing song production and song perch height, and that they sing during the breeding and non-breeding seasons to defend year-round territories. Collectively, our study supports the mate attraction and territory defence hypotheses of bird song.

openother-openSep 2023View details →

Mothers in a cooperatively breeding bird increase investment per offspring at the pre-natal stage when they will have more help with post-natal care

In many cooperative societies, including our own, helpers assist with the post-natal care of breeders’ young and may thereby benefit the post-natal development of offspring. Here, we present evidence of a novel mechanism by which such post-natal helping could also have beneficial effects on pre-natal development: By lightening post-natal maternal workloads, helpers may allow mothers to increase their pre-natal investment per offspring. We present the findings of a decade-long study of cooperatively breeding white-browed sparrow-weaver, Plocepasser mahali, societies. Within each social group, reproduction is monopolized by a dominant breeding pair, and non-breeding helpers assist with nestling feeding. Using a within-mother reaction norm approach to formally identify maternal plasticity, we demonstrate that when mothers have more female helpers, they decrease their own post-natal investment per offspring (feed their nestlings at lower rates) but increase their pre-natal investment per offspring (lay larger eggs, which yield heavier hatchlings). That these plastic maternal responses are predicted by female helper number, and not male helper number, implicates the availability of post-natal helping per se as the likely driver (rather than correlated effects of group size), because female helpers feed nestlings at substantially higher rates than males. We term this novel maternal strategy “maternal front-loading” and hypothesize that the expected availability of post-natal help either allows or incentivizes helped mothers to focus maternal investment on the pre-natal phase, to which helpers cannot contribute directly. The potential for post-natal helping to promote pre-natal development further complicates attempts to identify and quantify the fitness consequences of helping.

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Data for: The relationships of breeding stage to daytime singing behaviour and song perch height in Bermuda White-eyed Vireos (Vireo griseus bermudianus)

Open the record for dataset details and reuse information.

publicApr 2023View details →

opencc-zeroDec 2018View details →

Data from: Seasonal differences in baseline innate immune function are better explained by environment than annual cycle stage in a year-round breeding tropical songbird

1. Seasonal variation in innate immunity is often attributed to either temporal environmental variation or to life history trade-offs that arise from specific annual cycle stages but decoupling them is difficult in natural populations. 2. Here, we effectively decouple seasonal environmental variation from annual cycle stage effects by exploiting cross-seasonal breeding and moult in the tropical Common Bulbul Pycnonotus barbatus. We test how annual cycle stage interacts with a key seasonal environmental variable, rainfall, to determine immunity at population and individual level. If immune challenge varies with precipitation, we might expect immune function to be higher in the wet season due to increased environmental productivity. If breeding or moult imposes resource constraints on birds, depending on or independent of precipitation, we might expect lower immune indices during breeding or moult. 3. We sampled blood from 818 birds in four annual cycle stage categories: breeding, moult, simultaneous breeding and moulting, or neither. We quantified indices of innate immunity (haptoglobin, nitric oxide (NOx) and ovotransferrin concentrations, and haemagglutination and haemolysis titres) over two annual cycles of wet and dry seasons. 4. Environment (but not annual cycle stage or interactions between both) explained variation in all immune indices, except NOx. NOx concentration differed between annual cycle stages but not between seasons. However, within the wet season, haptoglobin, NOx, ovotransferrin and haemolysis differed significantly between breeding and non-breeding females. Aside from some recorded inconsistences, population level results were largely similar to results within individuals that were measured repeatedly. Unexpectedly, most immune indices were higher in the dry season and during breeding. 5. Higher immune indices may be explained if fewer or poorer quality resources force birds to increase social contact, thereby exposing individuals to novel antigens and increased infection risk, independently of environmental productivity. Breeding birds may also show higher immunity if less immune-competent and/or infected females omit breeding. We conclude that seasonal environmental variation impacts immunity more directly in natural animal populations than via resource trade-offs. In addition, immune indices were more often variable within than among individuals, but some indices are characteristic of individuals, and so may offer selective advantages if heritable.

opencc-zeroNov 2015View details →

Data from: Baseline immune activity is associated with date rather than with moult stage in the Arctic-breeding barnacle goose (Branta leucopsis)

Variation in immune defence in birds is often explained either by external factors such as food availability and disease pressure or by internal factors such as moult and reproductive effort. We explored these factors together in one sampling design by measuring immune activity over the time frame of the moulting period of Arctic-breeding barnacle geese (Branta leucopsis). We assessed baseline innate immunity by measuring levels of complement-mediated lysis and natural antibody-mediated agglutination together with total and differential leukocyte counts. Variation in immune activity during moult was strongly associated with calendar date and to a smaller degree with the growth stage of wing feathers. We suggest that the association with calendar date reflected temporal changes in the external environment. This environmental factor was further explored by comparing the immune activity of geese in the Arctic population with conspecifics in the temperate climate zone at comparable moult stages. In the Arctic environment, which has a lower expected disease load, geese exhibited significantly lower values of complement-mediated lysis, their blood contained fewer leukocytes, and levels of phagocytic cells and reactive leukocytes were relatively low. This suggests that lower baseline immune activity could be associated with lower disease pressure. We conclude that in our study species, external factors such as food availability and disease pressure have a greater effect on temporal variation of baseline immune activity than internal factors such as moult stage.

opencc-zeroDec 2015View details →

Data from: Testosterone production ability predicts breeding success and tracks breeding stage in male finches

Testosterone (T) is an important mediator of reproductive behaviours and potential target for selection. However, there are few data relating natural variation in T to fitness estimates. Here, we used the GnRH challenge (an injection of gonadotropin-releasing hormone which stimulates maximal T release), to examine how individual differences in T relate to reproductive success and how T changes across date and breeding stage. We measured pre- and post-challenge T, in captive male Gouldian finches (Erythrura gouldiae), before and after introducing females, and across breeding stage. Post-challenge T before introducing females positively predicted breeding success. Post-challenge T levels were unrelated to date, but strongly related to stage; T production ability was strongly attenuated in incubating males. Prechallenge T levels related only to date. Our results suggest that T production ability is an important target for selection and that when males invest heavily in parental care they reduce their sensitivity to GnRH.

opennotspecifiedDec 2017View details →

FIGURE 1 in DNA barcode for identification of immature stages of sand flies (Diptera: Psychodidae) collected from natural breeding sites

FIGURE 1. Neighbor-joining analysis of mitochondrial COI sequences of immature stages of sand flies isolated from natural breeding sites, contrasted with COI gene sequences from adults from GenBank. The black triangles represent the larvae and pupae identified.

Fig. 8 in What do Eumerus Meigen larvae feed on? New immature stages of three species (Diptera: Syrphidae) breeding in different plants

Fig. 8 "Bipartite" network between Eumerus species (right) and the genera of host plants (left). Length of the boxes show the number of interactions. Colors of the plant boxes: in red (dark color), genera with at least one species with economic value; in blue (light color), without economic value. Plant genera followed by plant family abbreviations as in Table 1

Fig. 4 in What do Eumerus Meigen larvae feed on? New immature stages of three species (Diptera: Syrphidae) breeding in different plants

Fig. 4 Anterior spiracles (AS) of Eumerus larvae and puparia, apicoventral view. a Eumerus alpinus, puparium; SEM. b Eumerus figurans, larva; stereo microscope. c Eumerus superbus, puparium; SEM. O spiracular opening. Scale lines: a = 50 μm; b = 200 μm; c = 100 μm

Fig. 1 in What do Eumerus Meigen larvae feed on? New immature stages of three species (Diptera: Syrphidae) breeding in different plants

Fig. 1 General shape of Eumerus puparia, dorsal view. a Eumerus alpinus. b Eumerus superbus. Scale lines: a and b = 2 mm

Fig. 3 in What do Eumerus Meigen larvae feed on? New immature stages of three species (Diptera: Syrphidae) breeding in different plants

Fig. 3 Head skeletons of Eumerus, lateral view. a Eumerus alpinus. b Eumerus figurans. c Eumerus superbus. D dorsal cornu, L mandibular lobe, M mandibular hook, P pharyngeal ridges, T accessory tooth, V ventral cornu. Scale lines = 250 μm

Fig. 7 in What do Eumerus Meigen larvae feed on? New immature stages of three species (Diptera: Syrphidae) breeding in different plants

Fig. 7 Total count of described early stages of Eumerus (triangles) and total count of known life cycles of early stages of Eumerus species (squares) by the first time a host-plant interaction was reported. X-axis shows years. Y-axis, number of Eumerus species

Fig. 6 in What do Eumerus Meigen larvae feed on? New immature stages of three species (Diptera: Syrphidae) breeding in different plants

Fig. 6 Posterior respiratory processes (PRP) of Eumerus larvae and puparia in dorsal view (left) and polar view (right). a, b Eumerus alpinus, puparium; SEM. c, d Eumerus figurans, larva; stereo microscope. e, f Eumerus superbus, puparium; SEM. α distance from the transverse ridge to the center of the spiracular plate, β width of the PRP at the transverse ridge level, C* spiracular scar, O spiracular opening, R transverse ridge, S spiracular seta. Scale lines: a and e = 500 μm; b and c = 250 μm; d = 100 μm; f = 200 μm

Fig. 5 in What do Eumerus Meigen larvae feed on? New immature stages of three species (Diptera: Syrphidae) breeding in different plants

Fig. 5 Pupal spiracles (PS) of Eumerus puparia (left) and details of the tubercles bearing spiracular openings (right). a, b Eumerus alpinus. c, d Eumerus superbus. O spiracular opening. Scale lines: a = 100 μm; b and d = 50 μm; c = 250 μm

Fig. 9 in What do Eumerus Meigen larvae feed on? New immature stages of three species (Diptera: Syrphidae) breeding in different plants

Fig. 9 Feeding network between larvae of Eumerus species (left, in gray) and plant tissues they feed on (right, colored) based on the interactions historically reported in bibliography for different genera of plants. Links between sides indicate relationships. Scales on each segment show the number of interactions established with the counter side. Plant tissue color palette as follows: tuber (yellow), swollen root (orange), rhizome (brown), processed material (black), fruits (red), stem (light green), corm (purple), cone (pink), and bulb (blue). Picture made using "circlize" package for R software