Lifting the Vendace, Coregonus albula, on the Life Table: Survival, Growth and Reproduction in Different Life-Stages during Very High and Low Abundance Regimes

Abstract Several species of willowherb (Epilobium) are considered as agricultural weeds and their prevalence has become an increasing problem in agriculture. The aim of this study was to investigate the role of willowherb plants in the initial stage of vegetation succession a year after the use of glyphosate. The study was based on the examination of thirteen willowherb specimens collected in the apple orchard of 0.2 ha area in August 2008, one month after glyphosate treatment, and vegetation field investigations in the same orchard in July 2009. The coverage of herb layer, the abundance and life stages of Epilobium plants in twenty plots of 1 m2 in size were investigated. The specimens of willowherbs, which survived the glyphosate application in 2008, were identified as Epilobium ciliatum and E. tetragonum. A year after the glyphosate treatment, the willowherb plants prevailed in the vegetation. One alien (E. ciliatum) and three native (E. hirsutum, E. parviflorum and E. tetragonum) species of willowherb were found. E. ciliatum was the most abundant. This species was characterized by the highest number of reproductive and virginile plants. E. parviflorum and E. tetragonum plants were abundant with a very high proportion of reproductive plants. Only pre-reproductive plants of E. hirsutum occurred in the study plots. The reproductive plants represented more than one third of the total number of willowherb plants. The distribution patterns of willowherb species in the plots were very variable.

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Glide analysis and bone strength tests indicate powered flight capabilities in hatchling pterosaurs

10.7287/peerj.preprints.3216 ◽

2017 ◽

Author(s):

Mark P Witton ◽

Elizabeth Martin-Silverstone ◽

Darren Naish

Keyword(s):

Growth Rate ◽

Body Weight ◽

Bone Strength ◽

Bending Strength ◽

Skeletal Development ◽

Maximum Size ◽

Strength Analysis ◽

Life Stages ◽

Strength Tests ◽

Very High

Pterosaur embryos and ‘hatchling’ specimens show a surprising level of skeletal development including well-ossified skeletons and large wings. This has prompted interpretations of pterosaurs as being flight-capable from the earliest ontogenetic stages, contrasting them against the majority of other flying animals, living or extinct. Though popular, this hypothesis is not universally accepted. Some authors propose that pterosaurs only became flight capable once they reached 50% of maximum size, explaining a slowing of growth rate in later ontogeny as metabolic resources were diverted into an energy-demanding form of locomotion. We investigated these hypotheses through glide performance and wing bone strength analysis on hatchling-grade specimens of two pterosaurs, Pterodaustro guinazui and Sinopterus dongi. We found that hatchling pterosaurs were excellent gliders, but with a wing ecomorphology more comparable to powered fliers than obligate gliders. Bone strength analysis shows that hatchling pterosaur wing bones are structurally identical to those of larger pterosaurs and – because of their very low body masses – their bending strength relative to body weight is very high, comparable to or exceeding the greatest values estimated for larger, more mature pterosaurs. Hatchling pterosaurs are thus as mechanically adapted to powered flight stresses as other pterosaurs, if not moreso. Together with our glide tests, this result supports interpretations of hatchling pterosaurs as flight-capable. Size differences between pterosaur hatchlings and larger members of their species dictate differences in wing ecomorphology and flight capabilities at different life stages, which might have bearing on pterosaur ontogenetic niching.

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Maternal care in Omaspides bistriata Boheman (Coleoptera: Chrysomelidae: Cassidinae: Mesomphaliini)

REVISTA CHILENA DE ENTOMOLOGÍA ◽

10.35249/rche.46.4.20.07 ◽

2020 ◽

Vol 46 (4) ◽

pp. 613-622

Author(s):

Rolando Ramírez C. ◽

Marcela Sánchez-Ocampo

Keyword(s):

Larval Development ◽

Life Table ◽

Maternal Care ◽

Feeding Habits ◽

Survival Curve ◽

Pupal Stage ◽

Larval Period ◽

Life Stages ◽

Stages Of Development

Maternal care (subsociality): characterization of the different stages of maternal care and its efficiency as a strategy. Maternal care and larval development of Omaspides bistriata Boheman, 1862 (Coleoptera: Chrysomelidae: Cassidinae: Mesomphaliini) are described; including characteristics and manner in which maternal care is given across the different stages of development of the specie (eggs, larvae, pupae and teneral adults). We report the oviposition of eggs, the duration to hatch the eggs, and the duration of larval period, pupal stage, and emergence. A life table and survival curve is presented covering all life stages. Changes in the behavior and feeding habits are also noted for the immatures and the attending mother.

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Life in the Slow Lane: Ecology and Conservation of Long-Lived Marine Animals

Life in the Slow Lane: Ecology and Conservation of Long-Lived Marine Animals ◽

10.47886/9781888569155.ch15 ◽

1999 ◽

Keyword(s):

Human Perception ◽

Marine Species ◽

Life Stages ◽

Marine Animals ◽

Marine Turtles ◽

Species Vulnerability ◽

Long Line ◽

Human Perturbations ◽

Population Maintenance ◽

Very High

<em>Abstract.</em> —Long-lived marine species are particularly vulnerable to human perturbations for reasons related both to the species’ demographics and human perception. Marine turtles provide an illustrative example: species delay maturity from 10 to as late as 30–60 years, and human monitoring of turtle populations focuses primarily on nesting adult females and nest production. Apparently marine turtles are trading early reproduction for later reproduction at a larger size, facilitating higher fecundity to overcome variable, often very high, natural mortality in eggs and early life stages. Human perturbations increase mortality of marine turtles at all life stages. However, population modeling has shown that annual survival of some stages, particularly large juveniles and adults, may be particularly critical to population maintenance and recovery. At the same time, monitoring focused on the larger, usually older, life stages of long-lived marine species may be a relatively poor indicator of actual population health and trends. High bycatch of long-lived marine species in long-line fisheries is outlined and concerns raised. Precautions, based on long-lived species’ vulnerability and the limitations of our ability to adequately monitor population status, should be built into management regimes.

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Glide analysis and bone strength tests indicate powered flight capabilities in hatchling pterosaurs

10.7287/peerj.preprints.3216v1 ◽

2017 ◽

Author(s):

Mark P Witton ◽

Elizabeth Martin-Silverstone ◽

Darren Naish

Keyword(s):

Growth Rate ◽

Body Weight ◽

Bone Strength ◽

Bending Strength ◽

Skeletal Development ◽

Maximum Size ◽

Strength Analysis ◽

Life Stages ◽

Strength Tests ◽

Very High

Pterosaur embryos and ‘hatchling’ specimens show a surprising level of skeletal development including well-ossified skeletons and large wings. This has prompted interpretations of pterosaurs as being flight-capable from the earliest ontogenetic stages, contrasting them against the majority of other flying animals, living or extinct. Though popular, this hypothesis is not universally accepted. Some authors propose that pterosaurs only became flight capable once they reached 50% of maximum size, explaining a slowing of growth rate in later ontogeny as metabolic resources were diverted into an energy-demanding form of locomotion. We investigated these hypotheses through glide performance and wing bone strength analysis on hatchling-grade specimens of two pterosaurs, Pterodaustro guinazui and Sinopterus dongi. We found that hatchling pterosaurs were excellent gliders, but with a wing ecomorphology more comparable to powered fliers than obligate gliders. Bone strength analysis shows that hatchling pterosaur wing bones are structurally identical to those of larger pterosaurs and – because of their very low body masses – their bending strength relative to body weight is very high, comparable to or exceeding the greatest values estimated for larger, more mature pterosaurs. Hatchling pterosaurs are thus as mechanically adapted to powered flight stresses as other pterosaurs, if not moreso. Together with our glide tests, this result supports interpretations of hatchling pterosaurs as flight-capable. Size differences between pterosaur hatchlings and larger members of their species dictate differences in wing ecomorphology and flight capabilities at different life stages, which might have bearing on pterosaur ontogenetic niching.

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Gonadulins, the fourth type of Insulin-related peptides in Decapods

10.1101/2020.03.19.998484 ◽

2020 ◽

Cited By ~ 1

Author(s):

Jan A. Veenstra

Keyword(s):

High Expression ◽

Portunus Trituberculatus ◽

Decapod Crustaceans ◽

Short Read ◽

Fourth Type ◽

Different Types ◽

Regulation Of Growth ◽

Very High ◽

Sagmariasus Verreauxi ◽

Growth And Reproduction

AbstractInsulin and related peptides play important roles in the regulation of growth and reproduction. Until recently three different types of insulin-related peptides had been identified from decapod crustaceans. The identification of two novel insulin-related peptides from Sagmariasus verreauxi and Cherax quadricarinatus suggested that there might a fourth type. Publicly available short read archives show that orthologs of these peptides are commonly present in these animals. Most decapods have two genes coding such peptides, but Penaeus species have likely only one and some palaemonids have three. Interestingly, expression levels can vary more than thousand-fold in the gonads of Portunus trituberculatus, where gonadulin 1 is expressed by the testis and gonadulin 2 by the ovary. Although these peptides are also expressed in other tissues, the occasionally very high expression in the gonads led to them being called gonadulins.

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Leaf damage has weak effects on growth and fecundity of common ragweed (Ambrosia artemisiifolia)

Botany ◽

10.1139/b09-110 ◽

2010 ◽

Vol 88 (2) ◽

pp. 158-164 ◽

Cited By ~ 12

Author(s):

A. Andrew M. MacDonald ◽

Peter M. Kotanen

Keyword(s):

Seed Production ◽

Natural Enemies ◽

Ambrosia Artemisiifolia ◽

Leaf Damage ◽

Enemy Release ◽

Insect Herbivores ◽

Stem Borers ◽

Common Ragweed ◽

Very High ◽

Growth And Reproduction

The Enemy Release Hypothesis predicts that exotic plants gain an advantage over native competitors by losing their natural enemies while invading new regions. However, this assumes that those enemies reduced the performance of these invaders in their native ranges, and this may not be true if an invader is highly tolerant of herbivory. We used a field experiment to test the herbivore tolerance of a North American annual, common ragweed (Ambrosia artemisiifolia L.), which is known to have lost insect herbivores while invading Europe. We clipped leaves to simulate damage by folivores and removed meristems to simulate apical mortality caused by stem borers, and measured the consequences for growth and reproduction. Stem biomass was only reduced by defoliation far in excess of native-range natural damage, while seed production was unaffected by our treatments. Severely damaged plants maintained seed production by allocating relatively more aboveground biomass to reproduction. These results suggest that for the most part, damage by natural enemies may have little impact on this highly tolerant plant; consequently, enemy release may not have provided a significant advantage to this species in Europe. As well, biological control by insect folivores is unlikely to succeed unless it results in very high levels of damage.

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Demographic Evaluation of Red Mite, Tetranychus bioculatus (Wood-Mason) on Different Ornamental Hosts

Journal of Agriculture & Rural Development ◽

10.3329/jard.v6i1.1661 ◽

1970 ◽

Vol 6 (1) ◽

pp. 83-90 ◽

Cited By ~ 1

Author(s):

MA Taleb ◽

MA Sardar

Keyword(s):

Life History ◽

Life Table ◽

Host Plants ◽

Cycle Duration ◽

Life Stages ◽

Life Table Parameters ◽

Life History Data ◽

Generation Times ◽

Cosmos Bipinnatus ◽

Life Cycle Duration

The demographic characteristics of red mite, Tetranychus bioculatus were studied through life table construction based on life history data using leaves of three ornamental host plants viz., marigold (Tagetes sp.), rose (Rosa sp.) and cosmos (Cosmos bipinnatus) in the laboratory at temperature of 20.3Â±0.66oC and relative humidity of 75.25Â±3.30%. The life cycle duration of red mite from egg to adult was shortened when feeding on marigold leaves with no significant differences in duration of life stages consuming three different hosts. The fecundity ranged from 70.6 to 109.8 eggs per female and it significantly differed among the mites live on different host plants. The host plants influenced the life table parameters of T. bioculatus showing highest innate capacity of increase (rm) of 0.24 on marigold. The marigold and cosmos favors increase mite population by 2.2 and 1.5 times, respectively, which higher than those fed on rose in the generation times (GT) of 18.22 and 19.18 days. Key words: Red mite, ornamental host plants, life history, life table. doi:10.3329/jard.v6i1.1661 J Agric Rural Dev 6(1&2), 83-90, June 2008

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Kekuatan Simbolik Beras dalam Ritus Kehidupan Masyarakat Batak Toba

Anthropos Jurnal Antropologi Sosial dan Budaya (Journal of Social and Cultural Anthropology) ◽

10.24114/antro.v5i2.14922 ◽

2020 ◽

Vol 5 (2) ◽

pp. 183

Author(s):

Resmi Hutasoit ◽

Izak M. Lattu ◽

Ebenhaizer I Nuban Timo

Keyword(s):

Young People ◽

Qualitative Method ◽

Life Stages ◽

Literature Study ◽

Social Equality ◽

History Of ◽

The Rich ◽

Study Techniques ◽

Very High ◽

Or History

This article aims to analyze the background or history of rice used as a symbol of spirit strengthening in the rites of life stages in the Batak land which are carried out in the adat of marriage, free from distress, promotion, entering a new home also when the child is baptized. The method used is a qualitative method with interview, observation and literature study techniques. The results found that rice has a sacred value for the Batak people. Rice is generally owned by the rich and poor so that there is social equality so that using rice as a symbol of spirit strengthening. Rice provides physical needs for health. Human physical health is very influential on the human spirit. When giving rice in certain events there is an element of safety, when the rice is placed over the head and scattered. They use rice as a symbol in certain rites from generation to generation from their ancestors. Rice for the Batak has a very high historical value from the process of planting rice to rice. This paper contributes to traditional leaders and young people to preserve and understand the traditions of their ancestors.

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