Terrestrial reproduction and parental care drive rapid evolution in the trade-off between offspring size and number across amphibians

The trade-off between offspring size and number is central to life history strategies. Both the evolutionary gain of parental care or more favorable habitats for offspring development are predicted to result in fewer, larger offspring. However, despite much research, it remains unclear whether and how different forms of care and habitats drive the evolution of the trade-off. Using data for over 800 amphibian species, we demonstrate that, after controlling for allometry, amphibians with direct development and those that lay eggs in terrestrial environments have larger eggs and smaller clutches, while different care behaviors and adaptations vary in their effects on the trade-off. Specifically, among the 11 care forms we considered at the egg, tadpole and juvenile stage, egg brooding, male egg attendance, and female egg attendance increase egg size; female tadpole attendance and tadpole feeding decrease egg size, while egg brooding, tadpole feeding, male tadpole attendance, and male tadpole transport decrease clutch size. Unlike egg size that shows exceptionally high rates of phenotypic change in just 19 branches of the amphibian phylogeny, clutch size has evolved at exceptionally high rates in 135 branches, indicating episodes of strong selection; egg and tadpole environment, direct development, egg brooding, tadpole feeding, male tadpole attendance, and tadpole transport explain 80% of these events. By explicitly considering diversity in parental care and offspring habitat by stage of offspring development, this study demonstrates that more favorable conditions for offspring development promote the evolution of larger offspring in smaller broods and reveals that the diversity of parental care forms influences the trade-off in more nuanced ways than previously appreciated.

Live imaging of the Cryptosporidium parvum lifecycle reveals direct development of male and female gametes from type one meronts

Cryptosporidium is a leading infectious cause of diarrhea around the world associated with waterborne outbreaks, community spread, or zoonotic transmission. The parasite has significant impact on early childhood mortality, and infection is both consequence and cause of malnutrition and stunting. There is currently no vaccine, and treatment options are very limited. Cryptosporidium is a member of the Apicomplexa, and as typical for this protist phylum relies on asexual and sexual reproduction. In contrast to other Apicomplexa, like malaria parasite Plasmodium, Cryptosporidium's entire lifecycle unfolds in a single host in less than three days. Here we establish a model to image lifecycle progression in living cells, and observe, track, and compare nuclear division of asexual and sexual stage parasites. We establish the length and sequence of the cell cycles of all stages and map the developmental fate of parasites across multiple rounds of invasion and egress. We determine that the parasite executes an intrinsic program of three generations of asexual replication, followed by a single generation of sexual stages that is independent of environmental stimuli. We find no evidence for a morphologically distinct intermediate stage (the tetraploid type II meront) but demonstrate direct development of gametes from 8N type I meronts. The progeny of each meront is collectively committed to either asexual or sexual fate, but importantly, meronts committed to sexual fate give rise to both males and females. We define a Cryptosporidium lifecycle matching Tyzzer's original description and inconsistent with the coccidian lifecycle now shown in many textbooks.

“Indirect development” increases reproductive plasticity and contributes to the success of scyphozoan jellyfish in the oceans

Ecologists and evolutionary biologists have been looking for the key(s) to the success of scyphomedusae through their long evolutionary history in multiple habitats. Their ability to generate young medusae (ephyrae) via two distinct reproductive strategies, strobilation or direct development from planula into ephyra without a polyp stage, has been a potential explanation. In addition to these reproductive modes, here we provide evidence of a third ephyral production which has been rarely observed and often confused with direct development from planula into ephyra. Planulae of Aurelia relicta Scorrano et al. 2017 and Cotylorhiza tuberculata (Macri 1778) settled and formed fully-grown polyps which transformed into ephyrae within several days. In distinction to monodisk strobilation, the basal polyp of indirect development was merely a non-tentaculate stalk that dissolved shortly after detachment of the ephyra. We provide a fully detailed description of this variant that increases reproductive plasticity within scyphozoan life cycles and is different than either true direct development or the monodisk strobilation. Our observations of this pattern in co-occurrence with mono- and polydisk strobilation in Aurelia spp. suggest that this reproductive mode may be crucial for the survival of some scyphozoan populations within the frame of a bet-hedging strategy and contribute to their long evolutionary success throughout the varied conditions of past and future oceans.

Analysis of The Morphological Characteristics of Bush Frog Philautus spp. Gistel, 1848 (Anura: Rhacophoridae) from Mount Ungaran

Traditionally, the genus Philautus Gistel, 1848 contains small Rhacoporid frogs that lack vomerine teeth and a direct development tadpole stage. In Java, this genus consists of 3 species, including Philautus aurifasciatus, Philautus jacobsoni, and Philautus pallidipes. It is known that Philautus aurifasciatus and Philautus jacobsoni are sympatric species from Mount Ungaran and are morphologically difficult to distinguish. Therefore, information is needed through the phenetic characters of each population in the area to identify differences in their morphology. This study aimed to analyze the morphological characteristics of Bush Frog Philautus spp. on Mount Ungaran in terms of meristic character through a direct field survey and comparison methods. Furthermore, it was conducted by observing 32 specimens of Philautus spp. from Mount Ungaran and compared with the Philautus aurifasciatus from Mount Gede Pangrango with 18 meristic characters. The results showed that Philautus spp. is similar to Philautus aurifasciatus in terms of their meristic characters. The results of the meristic analysis showed that Philautus spp. has a variety of dorsal colors from brown, purple, green, and gray with two types of patterns including patterned groups (resembling letters H, X, and V) and abstract. Furthermore, the throat, stomach, and lower thighs are granular with three snout shapes (protruding, round, and sloping). It has a loreal oblique tympanum and canthus rostralis. The forelimbs are not webbed while the hindlimbs are half webbed, and the inner metatarsal is an elongated oval in shape. Meristic analysis provides a basis for strengthening the taxonomic status of Philautus spp on Mount Ungaran, as well as information the distribution in Mount Ungaran.

Prospects for innovative development of entrepreneurial activities in the agricultural sector

The experience of developed countries in recent years convincingly shows that increasing the efficiency of agro-industrial production is achieved mainly due to the intensification of the successful activities of innovators (i.e., the scientific and technical sphere of industry). The end result of innovation is the creation of innovations and their direct development in production, which will contribute to a systematic and increasingly progressive organizational, economic, technical and technological renewal and increase in the efficiency of agro-industrial production. Key words: entrepreneurship, innovative development, efficiency, business, production

Beech tree masting explains the inter-annual variation in the fall and spring peaks of Ixodes ricinus ticks with different time lags

Background: The tick Ixodes ricinus is an important vector of tick-borne diseases including Lyme borreliosis. In continental Europe, the nymphal stage of I. ricinus often has a bimodal phenology with a large spring/early summer peak and a smaller fall peak. While there is consensus about the origin of the spring nymphal peak, there are two alternative hypotheses for the fall nymphal peak, direct development versus delayed diapause. These two hypotheses make different predictions about the time lags of the correlations between the spring peak, the fall peak, and seed production (masting) by deciduous trees. Methods: To determine which hypothesis is most important for explaining the fall peak, we used data from a long-term surveillance study (15 years) on the density of I. ricinus nymphal ticks at 4 different elevation sites in an area of Switzerland that is endemic for Lyme borreliosis, and long-term data on the mast of the European beech tree from the literature. Results: I. ricinus nymphs had a bimodal phenology at the three lower elevation sites, but a unimodal phenology at the top elevation site. At the lower elevation sites, the density of nymphs (DON) in the fall was strongly correlated with the DON in the spring of the following year. The inter-annual variation in the densities of I. ricinus nymphs in the fall and spring were best explained by a 1-year versus a 2-year time lag with the beech tree masting index. Fall nymphs had higher fat content and are younger than spring nymphs. All of these observations are consistent with the direct development hypothesis for the fall peak of I. ricinus nymphs at our study site. Our study provides new insight into the complex bimodal phenology of this important disease vector. Conclusions: Public health officials in Europe should be aware that following a strong mast year, the DON will increase 1 year later in the fall and 2 years later in the spring and summer. Population ecology studies of I. ricinus should consider that the spring and fall peak in the same calendar year represent different generations of ticks.

BECOMING ΚΛΕΙΝΟΣ IN CRETE AND MAGNA GRAECIA: DIONYSIAC MYSTERIES AND MATURATION RITUALS REVISITED

This article reconsiders the historical and typological relation between Greek maturation rituals and Greek mystery religion. Particular attention is given to the word κλεινός (‘illustrious’) and its ritual uses in two roughly contemporary Late Classical sources: an Orphic-Bacchic funerary gold leaf from Hipponion in Magna Graecia and Ephorus’ account of a Cretan pederastic age-transition rite. In both contexts, κλεινός marks an elevated status conferred by initiation. (This usage finds antecedents in Alcman's Partheneia.) Without positing direct development between puberty rites and mysteries, the article argues on the basis of shared vocabulary and other ritual elements that age-transitions influenced the ideology of mystery cults. It is further claimed that puberty rites and mysteries performed similar functions in their respective social contexts, despite obvious differences of prestige and visibility. Age-transition rites have been analysed in Bourdieu's terms as ‘rites of institution’, in which young elites were publicly affirmed in civic roles: private mysteries can be described in analogous but opposed terms as rites of ‘counter-institution’, in which familiar ritual language and symbols of elite status were used to construct an alternative ‘imagined community’ of mystery initiates.

Ontogenetic Basis of Among-Generation Differences in Size-Related Traits in a Polyphenic Butterfly

Seasonal polyphenisms are cases in which individuals representing generations occurring in different times of the year systematically differ in their morphological, physiological, and/or behavioral traits. Such differences are often assumed to constitute adaptive responses to seasonally varying environments, but the evidence for this is still scarce. The adaptive character of the response would be corroborated by the pattern in which the decision about choosing a particular seasonal phenotype is made before the onset of respective environmental conditions (anticipatory plasticity). Alternatively, the between-generation differences can be caused by immediate effects of seasonally varying environments (responsive plasticity). Here we reared the larvae of the seasonally polymorphic map butterfly Araschnia levana under two different photoperiodic regimes, which provided different seasonal cues. These two treatments induced direct development and diapause pathways, respectively. Replicating the experiment at different temperatures and levels of host plant quality allowed us to evaluate both the anticipatory and the responsive components of the associated plastic changes in life-history traits. Larvae representing the direct development pathway invariably had higher growth rates and shorter development periods, although the difference between the developmental pathways was smaller at inferior host quality. Body size differences between the developmental pathways turned out to be less consistent, as the natural pattern of higher pupal mass of the directly developing individuals could only be reproduced at lower rearing temperature. Though being considerably modified by immediate environmental effects, the between-generation differences in size, growth rates, and larval are largely based on anticipatory plasticity (= responses to photoperiodic cues) and should be treated as seasonal adaptations in A. levana. In a more general context, we show how investigating the proximate basis of size differences can serve the purpose of identifying the limits of phenotypic plasticity in juvenile growth schedules.