Comparison of egg size and related life-history characteristics for two predaceous tree-hole mosquitoes (Toxorhynchites)

1980 ◽  
Vol 58 (11) ◽  
pp. 2065-2070 ◽  
Author(s):  
R. J. Lamb ◽  
S. M. Smith
Keyword(s):  
Life History ◽  
Egg Size ◽  
Prey Size ◽  
Prey Availability ◽  
Fourth Instar ◽  
Natural Environments ◽  
First Instar ◽  
Life History Characteristics ◽  
Tree Hole ◽  
Toxorhynchites Rutilus

Certain life-history characteristics of Toxorhynchites brevipalpis and Tx. rutilus septentrionalis were compared in the laboratory with the aim of accounting for a more than twofold difference in the weight of their eggs. First- and second-instar larvae of Tx. rutilus were longer and third-instar larvae shorter than corresponding stages of Tx. brevipalpis. The sizes of the two species did not differ appreciably in the later stages. Toxorhynchites rutilus first-instar larvae consumed more prey but total prey consumption was much greater for Tx. brevipalpis due to differences in consumption during the fourth instar. Developmental times from egg to adult did not differ at 25 °C. Toxorhynchites brevipalpis produced twice as many eggs per day during the first 14 days of oviposition but, due to size differences, the weight of the eggs produced per day was equal for the two species. Female Tx. brevipalpis laid an average of 5.9 eggs per oviposition flight. A corresponding value for Tx. rutilus was not determined. Newly hatched Tx. brevipalpis larvae withstood starvation for a longer period of time than Tx. rutilus larvae. Larval Tx. rutilus captured and consumed larger prey.It is hypothesized that egg size and fecundity are adapted to prey size and heterogeneity in prey availability in the natural environments of the two species.

The unity of characters: ecological and morphological specialisation in larvae of Hawaiian platynine Carabidae (Coleoptera)

2000 ◽  
Vol 14 (6) ◽  
pp. 931 ◽  
Author(s):  
James K. Liebherr
Keyword(s):  
Life History ◽  
Egg Size ◽  
Life History Traits ◽  
Phylogenetic Inference ◽  
Larval Period ◽  
Larval Duration ◽  
Similar Treatment ◽  
First Instar ◽  
Functional Linkage ◽  
History Information

Life history information and first instar egg bursters are compared for larvae of 25 species across the monophyletic radiation of Hawaiian Platynini (Coleoptera : Carabidae). The plesiotypic larval duration is approximately five weeks, with derived extension of the larval period having evolved during phylogenetic diversification of the radiation. This extension in larval duration is associated with vestigialisation of the metathoracic flight wings. Egg size is larger in those brachypterous species with slower developing larvae, reflecting pervasive ecological specialisation of these taxa in the isolated, favourable, and temporally stable habitats of Hawaiian montane forests. First instar egg bursters are also compared across these taxa, with evolution of a keel-like egg burster congruently defining a clade also characterised by longer larval duration and larger egg size. A functional linkage between egg burster configuration and egg size is rejected by lack of any association between egg size and egg burster type in the related genus Calathus. Such rejection does not reduce the value of the egg burster for phylogenetic inference. The ability to assess taxa for both life history traits and egg burster configuration argues for similar treatment of all such characters, both ecological and morphological, when estimating phylogeny.

Egg size and taxon: their influence on survival and development of chrysopid hatchlings after food and water deprivation

1991 ◽  
Vol 69 (10) ◽  
pp. 2644-2650 ◽  
Author(s):  
Catherine A. Tauber ◽  
Maurice J. Tauber ◽  
Michael J. Tauber
Keyword(s):  
Life History ◽  
Water Deprivation ◽  
Egg Size ◽  
Maternal Investment ◽  
Developmental Rate ◽  
Life History Variation ◽  
Larval Size ◽  
First Instar ◽  
Survival And Development ◽  
Phylogenetic Lineages

Genus- and species-level differences characterize the pattern of life-history variation in two distinct phylogenetic lineages of chrysopids, Chrysopa and Chrysoperla. Species in the genus Chrysopa exhibit significant variation in egg size, and this variation is positively correlated with the ability of hatchlings to withstand periods of food and water deprivation prior to their initial feeding. The variation is also significantly correlated with larval size, as measured by the tibial length of first-instar larvae. Although the six Chrysopa species differ in several other life-history traits (i.e, the incubation period and rate of first-instar larval development), the variation is unrelated to egg size. It appears that maternal allocation of resources to eggs largely serves to enhance embryonic growth and the survival of hatchlings during searching. That is, within the Chrysopa lineage egg size varies; larger eggs yield larger, more robust hatchlings. These hatchlings may or may not develop faster than congeners from small eggs. In comparison with Chrysopa, the genus Chrysoperla has less variability in egg size and developmental rate. Furthermore, although Chrysoperla eggs are relatively small, the ability of hatchlings to endure periods of food or water deprivation is at least as great as it is in the Chrysopa species with large eggs. We conclude that maternal investment in larval fitness has different ontogenetic pathways, ecological roles, and phylogenetic histories in the two genera.

Growth and development of larvae and adults of Tipula sacra Alexander (Insecta: Diptera) in a series of abandoned beaver ponds

1976 ◽  
Vol 54 (2) ◽  
pp. 266-284 ◽  
Author(s):  
G. Pritchard
Keyword(s):  
Growth Rate ◽  
Life History ◽  
Growth And Development ◽  
Adult Emergence ◽  
Head Capsule ◽  
Fourth Instar ◽  
Beaver Ponds ◽  
The Third ◽  
First Instar ◽  
Two Peaks

Collections of all stages of the crane fly, Tipula sacra have been made over a period of years from a series of abandoned beaver ponds in the Kananaskis Valley, Alberta. The growth of larvae was followed by head-capsule measurements and weights. Eggs hatch within a month; first-instar larvae grow rapidly and enter the second instar after a few weeks. The second instar may last for 3 months and the third instar usually lasts for 6 months, including the first winter. Most larvae spend almost a full year in the fourth instar and overwinter for a second time. However, there was much variation in growth rate within the population. Adult emergence curves were consistent in form in 4 years. Each spanned a period of just over 2 months, although individual adults lived for only a few days. These curves snowed two peaks, the second of which contained 15–20% of the year's emergents. These two groups may represent different cohorts that have grown at different rates, suggesting that the life history may be semivoltine or univoltine. The sex ratio changes from about 1:1 in the third instar to 2:1 in favor of males in the late fourth instar, pupa, and adult.

Life History and Abundance of Mysis relicta in Lake Michigan

1978 ◽  
Vol 35 (9) ◽  
pp. 1165-1170 ◽  
Author(s):  
Mark D. Morgan ◽  
Alfred M. Beeton
Keyword(s):  
Life History ◽  
Key Words ◽  
Lake Michigan ◽  
Fourth Instar ◽  
Mysis Relicta ◽  
First Instar ◽  
Males And Females

Mysis relicta was sampled in Lake Michigan approximately monthly with an epibenthic sled, August 1975–July 1976. Total numbers ranged from a low of 23 m−2 in February to a high of 337 m−2 in May and averaged 188 m−2. It was possible to partition the population into five instars. Major peaks in proportions of first instar individuals occurred in March, July, and November. It took about 1 yr for first instar individuals to reach the fourth instar. Growth averaged a little less than 1 mm/mo. Males and females reached maturity and bred in the fourth instar, so females produced their first brood at 1 yr of age. Males died at this time, but females were found to molt to the fifth instar, mate, and produce a second brood approximately 4 mo later. Key words: Mysis relicta, Lake Michigan, life history, abundance

Biology of tree-hole mosquitoes: photoperiodic control of development in northern Toxorhynchites rutilus (Coq.)

1975 ◽  
Vol 53 (7) ◽  
pp. 889-893 ◽  
Author(s):  
William E. Bradshaw ◽  
Christina M. Holzapfel
Keyword(s):  
Rapid Growth ◽  
Fourth Instar ◽  
Photoperiodic Control ◽  
The Third ◽  
Winter Conditions ◽  
Tree Hole ◽  
Critical Photoperiod ◽  
Northern Portion ◽  
Toxorhynchites Rutilus ◽  
Short Days

Carnivorous larvae of the tree-hole mosquito, Toxorhynchites rutilus, were collected from the northern portion of their range. Long days were found to promote rapid growth and metamorphosis from egg to adult; short days retard development during the second and third instars and evoke diapause in the fourth. All larvae exposed continuously to long days from embryos to the third or fourth instar developed without entering diapause. Diapause-averting long days experienced earlier in development could be reversed in at least some individuals by subsequent short days. Among laboratory-reared larvae or those caught early in the fall, the critical photoperiod for the maintenance of diapause is around 13 h of light per day. Among larvae caught in midwinter, diapause is not maintained in all larvae at any photoperiod and in 50% or less of the larvae at photophases shorter than 12.5 h. Winter conditions in the northern part of the range of T. rutilus appear to play a prominent role in the maintenance and termination of diapause.

scholarly journals Importance of prey size on investigating prey availability of larval fishes

PLoS ONE ◽  
2021 ◽  
Vol 16 (5) ◽  
pp. e0251344
Author(s):  
Yu-Hsuan Huang ◽  
Hsiao-Hang Tao ◽  
Gwo-Ching Gong ◽  
Chih-hao Hsieh
Keyword(s):  
Prey Size ◽  
Prey Availability ◽  
Larval Fish ◽  
Mesh Size ◽  
Fish Density ◽  
Natural Environments ◽  
Positive Relationships ◽  
Larval Fishes ◽  
Important Prey ◽  
The Relationship

Prey availability plays an important role in determining larval fish survival. Numerous studies have found close relationships between the density of mesozooplankton and larval fishes; however, emerging studies suggest that small-size zooplankton are more important prey for some larval fish species. One arising question is whether the size of zooplankton determines the relationship between zooplankton and larval fish community in natural environments. To address this question, we collected small-size (50–200 μm) zooplankton, mesozooplankton (> 330 μm), and larval fish using three different mesh-size (50, 330, 1000 μm, respectively) nets in the East China Sea, and examined their relationships in density. Both meso- and small-size zooplankton densities showed positive relationships with larval fish density, while the relationship is much stronger for the small-size zooplankton. Specifically, the smallest size classes (50–75 and 75–100 μm) of small-size zooplankton showed the highest positive relationships with larval fish density. Temperature, salinity, and chlorophyll-a concentration did not significantly explain larval fish density. Based on these findings, we demonstrate the importance of considering prey size when investigating prey availability for larval fishes.

Geographic variation in development time and predation in the tree-hole mosquito, Toxorhynchites rutilus septentrionalis (Diptera: Culicidae)

1978 ◽  
Vol 56 (10) ◽  
pp. 2156-2165 ◽  
Author(s):  
R. M. Trimble ◽  
Stephen M. Smith
Keyword(s):  
Development Time ◽  
Adult Emergence ◽  
First Instar ◽  
Emergence Success ◽  
Tree Hole ◽  
Daily Rate ◽  
Proportional Increase ◽  
Laboratory Colonies ◽  
Toxorhynchites Rutilus ◽  
Biological Differences

In laboratory colonies of a northern (Newark, DE) and southern (Lake Charles, LA) population of Tx. r. septentrionalis the proportional increase or decrease in total development time with changes in temperature did not vary significantly. Between 13 and 27 °C, development of the third- and fourth-instar larvae, pupae, and preadults was completed more rapidly in the Delaware population. By contrast, Louisiana eggs embryonated more rapidly than Delaware eggs. Survival from the first instar to adult emergence was similar in both populations between 13 and 29 °C; however, all Louisiana larvae that pupated also emerged, whereas the emergence success of Delaware pupae declined with each 2 °C decrease in temperature between 23 and 13 °C. Louisiana larvae consumed more prey during development because they took longer to develop and because their daily rate of prey consumption was greater than that of Delaware larvae. Louisiana larvae partly consumed and killed without consuming more prey during development. These differences are discussed in relation to climatological and possible biological differences in the environments from which each population was derived.

scholarly journals Prey Size Decline as a Unifying Ecological Selecting Agent in Pleistocene Human Evolution

Quaternary ◽  
2021 ◽  
Vol 4 (1) ◽  
pp. 7
Author(s):  
Miki Ben-Dor ◽  
Ran Barkai
Keyword(s):  
Prey Size ◽  
Prey Availability ◽  
Stone Tool ◽  
Foraging Efficiency ◽  
Energetic Cost ◽  
Large Prey ◽  
Biomass Density ◽  
Cultural Changes ◽  
Progressive Decline ◽  
Brain Expansion

We hypothesize that megafauna extinctions throughout the Pleistocene, that led to a progressive decline in large prey availability, were a primary selecting agent in key evolutionary and cultural changes in human prehistory. The Pleistocene human past is characterized by a series of transformations that include the evolution of new physiological traits and the adoption, assimilation, and replacement of cultural and behavioral patterns. Some changes, such as brain expansion, use of fire, developments in stone-tool technologies, or the scale of resource intensification, were uncharacteristically progressive. We previously hypothesized that humans specialized in acquiring large prey because of their higher foraging efficiency, high biomass density, higher fat content, and the use of less complex tools for their acquisition. Here, we argue that the need to mitigate the additional energetic cost of acquiring progressively smaller prey may have been an ecological selecting agent in fundamental adaptive modes demonstrated in the Paleolithic archaeological record. We describe several potential associations between prey size decline and specific evolutionary and cultural changes that might have been driven by the need to adapt to increased energetic demands while hunting and processing smaller and smaller game.

Life history characteristics of an invasive cyprinid fish (Carassius gibelio) in Chimaditis Lake (northern Greece)

2008 ◽  
Vol 24 (2) ◽  
pp. 213-217 ◽  
Author(s):  
I. D. Leonardos ◽  
A. C. Tsikliras ◽  
V. Eleftheriou ◽  
Y. Cladas ◽  
I. Kagalou ◽  
...  
Keyword(s):  
Life History ◽  
Cyprinid Fish ◽  
Northern Greece ◽  
Carassius Gibelio ◽  
Life History Characteristics

Adaptive strategies and life history characteristics in a warming climate: Salmon in the Arctic?

2012 ◽  
Vol 96 (10-11) ◽  
pp. 1187-1226 ◽  
Author(s):  
Jennifer L. Nielsen ◽  
Gregory T. Ruggerone ◽  
Christian E. Zimmerman
Keyword(s):  
Life History ◽  
Adaptive Strategies ◽  
The Arctic ◽  
Warming Climate ◽  
Life History Characteristics
Sign in / Sign up

Export Citation Format

Share Document