Life history and environmental inference through retrospective morphometric analysis of bryozoans: a preliminary study

2000 ◽  
Vol 80 (6) ◽  
pp. 1127-1128 ◽  
Author(s):  
Aaron O'Dea ◽  
Beth Okamura
Keyword(s):  
Primary Productivity ◽  
Life Histories ◽  
Colony Growth ◽  
Bay Of Fundy ◽  
Seasonal Fluctuations ◽  
Temperature Regimes ◽  
Morphometric Analyses ◽  
Thermal Regimes ◽  
Preliminary Study ◽  
Flustra Foliacea

A preliminary comparative analysis of colony growth and zooid size in the perennial bryozoan Flustra foliacea (Bryozoa: Cheilostomatida) reveals reduced colony growth in the Bay of Fundy relative to growth in the Menai Straits and the Skagerrak, while seasonal fluctuations in zooid size are in synchrony with temperature regimes. Such retrospective morphometric analyses may allow inferences of primary productivity and thermal regimes and provide insights into the life histories of both Recent and fossil bryozoans.

scholarly journals Specificity of genome evolution in experimental populations ofEscherichia colievolved at different temperatures

2017 ◽  
Vol 114 (10) ◽  
pp. E1904-E1912 ◽  
Author(s):  
Daniel E. Deatherage ◽  
Jamie L. Kepner ◽  
Albert F. Bennett ◽  
Richard E. Lenski ◽  
Jeffrey E. Barrick
Keyword(s):  
Temperature Treatment ◽  
The Other ◽  
Isolated Populations ◽  
Signature Genes ◽  
Genomic Signatures ◽  
Local Environments ◽  
Temperature Regimes ◽  
Thermal Regimes ◽  
Different Temperatures ◽  
C 32

Isolated populations derived from a common ancestor are expected to diverge genetically and phenotypically as they adapt to different local environments. To examine this process, 30 populations ofEscherichia coliwere evolved for 2,000 generations, with six in each of five different thermal regimes: constant 20 °C, 32 °C, 37 °C, 42 °C, and daily alternations between 32 °C and 42 °C. Here, we sequenced the genomes of one endpoint clone from each population to test whether the history of adaptation in different thermal regimes was evident at the genomic level. The evolved strains had accumulated ∼5.3 mutations, on average, and exhibited distinct signatures of adaptation to the different environments. On average, two strains that evolved under the same regime exhibited ∼17% overlap in which genes were mutated, whereas pairs that evolved under different conditions shared only ∼4%. For example, all six strains evolved at 32 °C had mutations innadR, whereas none of the other 24 strains did. However, a population evolved at 37 °C for an additional 18,000 generations eventually accumulated mutations in the signature genes strongly associated with adaptation to the other temperature regimes. Two mutations that arose in one temperature treatment tended to be beneficial when tested in the others, although less so than in the regime in which they evolved. These findings demonstrate that genomic signatures of adaptation can be highly specific, even with respect to subtle environmental differences, but that this imprint may become obscured over longer timescales as populations continue to change and adapt to the shared features of their environments.

Individual condition, standard metabolic rate, and rearing temperature influence steelhead and rainbow trout (Oncorhynchus mykiss) life histories

2014 ◽  
Vol 71 (4) ◽  
pp. 491-501 ◽  
Author(s):  
Matthew R. Sloat ◽  
Gordon H. Reeves
Keyword(s):  
Life Histories ◽  
Somatic Growth ◽  
High Standard ◽  
Standard Metabolic Rate ◽  
Temperature Treatment ◽  
Individual Growth ◽  
Whole Body ◽  
Rainbow Trout Oncorhynchus Mykiss ◽  
Thermal Regimes ◽  
The Relationship

We reared juvenile Oncorhychus mykiss with low and high standard metabolic rates (SMR) under alternative thermal regimes to determine how these proximate factors influence life histories in a partially migratory salmonid fish. High SMR significantly decreased rates of freshwater maturation and increased rates of smoltification in females, but not males, after 1 year of rearing. Warmer water temperatures significantly decreased rates of freshwater maturation and increased rates of smoltification in both sexes. Variation in individual growth influenced the probability of adopting anadromy or freshwater residency as life histories, but produced paradoxical results. Individuals with the highest growth performance within their respective temperature treatments had a higher probability of freshwater maturation, but warmer temperatures decreased freshwater maturation despite significantly increasing somatic growth. Whole-body lipid content was significantly lower for fish reared in the warm temperature treatment, which may explain the decreased probability of freshwater maturation for individuals exposed to warmer temperatures. Our results indicate that changes in somatic growth induced by altered thermal regimes can influence the relationship between body size and the probability of maturation. Accordingly, somatic growth may not be a robust predictor of shifts in the prevalence of anadromy and residency in partially migratory salmonids when compared across thermal regimes.

A Preliminary Study of the Limnology of Lake Hayes

1952 ◽  
Vol 3 (1) ◽  
pp. 74 ◽  
Author(s):  
VH Jolly
Keyword(s):  
New Zealand ◽  
Vertical Distribution ◽  
Surface Waters ◽  
Vertical Migration ◽  
General Description ◽  
Seasonal Fluctuations ◽  
Direct Sunlight ◽  
Physical Conditions ◽  
Weak Light ◽  
Preliminary Study

A general description is given of Lake Hayes, a freshwater lake in the South Island of New Zealand, with a brief analysis of its physical conditions. Preliminary samplings from a variety of lakes showed that Lake Hayes possesses a comparatively rich zooplankton, noteworthy for the fact that its bulk is made up of few species, chiefly entomostracan Crustacea. The greatest number of organisims occur in the upper 6 fathoms but there is a vertical distribution through the complete range. Seasonal fluctuations are marked, the phytoplankton showing greatest productivity in spring, while summer and autumn peaks are dominated respectively by cladocera and copepods. The Entomostraca manifest a diurnal vertical migration. There is a concentration of the population in the surface waters at dawn and dusk. During the day, tile migrants desert the upper waters, while at night the numbers assume average proportions but no peak periods occur. It appears that the Entomostraca of Lake Hayes exhibit n facultative phototropism with a negative reaction to direct sunlight but a positive reaction to weak light.

Large pelagic predators could jeopardize the recovery of endangered Atlantic salmon

2014 ◽  
Vol 71 (3) ◽  
pp. 343-350 ◽  
Author(s):  
Gilles L. Lacroix
Keyword(s):  
Atlantic Salmon ◽  
Life Histories ◽  
Habitat Preferences ◽  
Bay Of Fundy ◽  
Coastal Zones ◽  
Apex Predators ◽  
Atlantic Bluefin Tuna ◽  
Archival Tags ◽  
Migration Strategies ◽  
The Impact

Long-term population viability of Bay of Fundy Atlantic salmon (Salmo salar) is threatened by high levels of marine mortality during migration. Pop-up satellite archival tags on repeat spawners provide direct evidence of extensive natural mortality of migrating salmon in coastal zones attributed to predation by large pelagic fish and no evidence of fishing mortality. Ingested tags show that salmon with a coastal migration are eaten by porbeagle shark (Lamna nasus) inside the Bay of Fundy, whereas distant migrants are consumed by Atlantic bluefin tuna (Thunnus thynnus) and other apex predators along the Scotian Shelf. Mortality is clustered in a few zones because of similar predator–prey habitat preferences and overlapping migration paths. The extent of predation in salmon populations with different migration strategies can account for observed decline rates in neighbouring populations with different life histories. The impact on endangered salmon populations that rely on multiple repeat spawners for population stability may be sufficient to hamper ongoing recovery efforts.

scholarly journals Using simulated temperature regimes to test growth and development of an invasive forest insect under climate change

2021 ◽  
Author(s):  
Jonathan A. Walter ◽  
Lily M. Thompson ◽  
Sean D. Powers ◽  
Dylan Parry ◽  
Salvatore J. Agosta ◽  
...  
Keyword(s):  
Climate Change ◽  
Growth Rates ◽  
Larval Growth ◽  
Transplant Experiment ◽  
Native Forest ◽  
Source Population ◽  
Climate Change Scenarios ◽  
Temperature Regimes ◽  
Thermal Regimes ◽  
Environmental Chambers

AbstractTemperature and its impact on fitness are fundamental for understanding range shifts and population dynamics under climate change. Geographic climate heterogeneity, behavioural and physiological plasticity, and thermal adaptation to local climates makes predicting the responses of species to climate change complex. Using larvae from seven geographically distinct wild populations in the eastern United States of the non-native forest pest Lymantria dispar dispar (L.), we conducted a simulated reciprocal transplant experiment in environmental chambers using six custom temperature regimes representing contemporary conditions near the southern and northern extremes of the US invasion front and projections under two climate change scenarios for the year 2050. Larval growth rates increased with climate warming compared to current thermal regimes and responses differed by population. A significant population-by-treatment interaction indicated that growth rates increased more when a source population experienced the warming scenarios for their region, especially for southern populations. Our study demonstrates the utility of simulating thermal regimes under climate change in environmental chambers and emphasizes how the impacts from future increases in temperature can be heterogeneous due to geographic differences in climate-related performance among populations.

Preliminary study of movements of harbor porpoises (Phocoena phocoena) in the Bay of Fundy using radiotelemetry

1975 ◽  
Vol 53 (10) ◽  
pp. 1466-1471 ◽  
Author(s):  
D. E. Gaskin ◽  
G. J. D. Smith ◽  
A. P. Watson
Keyword(s):  
New Brunswick ◽  
Bay Of Fundy ◽  
Southern Coast ◽  
Phocoena Phocoena ◽  
Dorsal Fin ◽  
Normal Behavior ◽  
Intermittent Contact ◽  
Preliminary Study ◽  
Time Average ◽  
Harbor Porpoises

Six harbor porpoises captured in herring weirs between September 1973 and September 1974 on the southern coast of New Brunswick were tagged and released. The three smallest animals were given visible dorsal fin tags, and the three larger specimens radiotelemetric packages attached to their dorsal fins. These animals were tracked using an ADFS-210 receiver coupled with a fixed-loop array on a 6.7-m mast antenna. Good signals were received at distances of up to 16 km using frequencies in the 26–28 MHz region. Most tracking problems resulted from interference from citizen-band operations and "skip" at certain times of the day and night. The transmitters appeared to cause little or no disruption of normal behavior in the larger animals. Intermittent contact was maintained for 2, 3, and 11 days respectively before the animals moved out of range. A total of 76 h, 29 min actual radiotracking time was recorded. Some tentative estimates of distances travelled per unit time, average swimming speeds, and apparent time spent foraging and feeding are tabulated.

scholarly journals Endangered Right Whales Enhance Primary Productivity in the Bay of Fundy

PLoS ONE ◽  
2016 ◽  
Vol 11 (6) ◽  
pp. e0156553 ◽  
Author(s):  
Joe Roman ◽  
John Nevins ◽  
Mark Altabet ◽  
Heather Koopman ◽  
James McCarthy
Keyword(s):  
Primary Productivity ◽  
Bay Of Fundy ◽  
Right Whales

Natural otolith microstructure patterns reveal precise homing to natal incubation sites by sockeye salmon (Oncorhynchus nerka)

1999 ◽  
Vol 77 (5) ◽  
pp. 766-775 ◽  
Author(s):  
Thomas P Quinn ◽  
Eric C Volk ◽  
Andrew P Hendry
Keyword(s):  
Life Histories ◽  
Sockeye Salmon ◽  
Spatial Scales ◽  
Oncorhynchus Nerka ◽  
Early Life History ◽  
Island Population ◽  
Otolith Microstructure ◽  
River Population ◽  
Thermal Regimes ◽  
Lake Washington

Experimental results suggest that anadromous salmon and trout learn (imprint) the odors of their natal site just prior to or during seaward migration. In contrast, information on the life histories of several species and the genetic structure of populations indicate that they must imprint earlier in life, probably during incubation in the gravel or when they emerge as free-swimming fry. To test the hypothesis that sockeye salmon (Oncorhynchus nerka) home to their incubation-emergence sites (rather than just to the lake where they reared before migrating to sea), we took advantage of the natural variation in otolith microstructure caused by differences in thermal regimes during incubation. We collected otoliths from adult sockeye salmon that returned to discrete spawning areas in Iliamna Lake, Alaska, and Lake Washington, Washington, and, in blind trials, these were classified based on comparison with otoliths from juveniles from the same sites and using information on site-specific thermal regimes. Our analysis showed that the salmon were much more likely to return to their natal incubation site than would have occurred by chance. Estimated straying rates were about 0.1% from the Woody Island population to the Pedro Pond population in Iliamna Lake and about 1% from the Cedar River population to the Pleasure Point population in Lake Washington. The results were consistent with genetic evidence for fine-scale structure of salmon populations and with conservation based on spatial scales appropriate for the early life history of the fish.

Preliminary assessment of human remains from the Temple of Hatshepsut at Deir el Bahari

2018 ◽  
Vol 27 (2) ◽  
pp. 117-128
Author(s):  
Roselyn A. Campbell
Keyword(s):  
Life Histories ◽  
Traumatic Injury ◽  
Human Remains ◽  
Future Research ◽  
Preliminary Assessment ◽  
Intermediate Period ◽  
The Third ◽  
Preliminary Study ◽  
The Temple ◽  
Third Intermediate Period

Excavations over the course of many seasons by the Polish-Egyptian Mission in the Temple of Hatshepsut at Deir el-Bahari have revealed the presence of multiple intrusive burials within and around the temple structure itself. These burials are dated much later than the construction of Hatshepsut’s temple, most of them seemingly from the Third Intermediate Period, and have been heavily disturbed over the millennia. This article presents a preliminary assessment of human remains from some of these burials. The remains are highly fragmentary and in varying states of preservation, from mummified to completely skeletonized. Only two individuals are present as nearly complete mummies. A brief inventory indicates the presence of multiple individuals, both adults and juveniles, and both male and female. At least one instance of a healed traumatic injury is visible in one of the mummified individuals. This preliminary study is intended to establish a foundation for future research regarding the life histories of these individuals.

scholarly journals Unique habitat and macroinvertebrate assemblage structures in spring-fed streams: a comparison among lowland tributaries and mainstreams in northern Japan

2020 ◽  
Author(s):  
Masaru Sakai ◽  
Katsuya Iwabuchi
Keyword(s):  
Primary Productivity ◽  
Standing Stock ◽  
Fine Sediment ◽  
River Networks ◽  
Canopy Openness ◽  
Macroinvertebrate Assemblage ◽  
Temperature Regimes ◽  
Periphyton Biomass ◽  
Stable Flow ◽  
Northern Japan

AbstractThe stable flow and temperature regimes of spring-fed streams are distinct from the dynamic regimes of other streams. We investigated differences in habitat and macroinvertebrate assemblages among a spring-fed tributary, an adjacent non-spring-fed tributary, and mainstream reaches. Current velocity was slowest in the spring-fed reach and percent fine sediment deposition was 3.8–13.9 times higher than in non-spring streams. Mean periphyton biomass was greatest in the mainstream reach where canopy openness was greatest, whereas the standing stock of detritus was greatest in the spring-fed reach. These results suggest that the stable flow regime in the spring-fed stream leads to the accumulation of fine sediment and detritus on the streambed. Oligochaeta and chironomids, which are burrower-gatherers, were remarkably abundant in the spring-fed reach and total macroinvertebrate abundance was 3.4–12.2 times greater than in the other reaches. Sprawler-grazer ephemeropterans were abundant in the mainstream reaches, likely due to higher primary productivity. Allomyia sp, which depend on cool spring-fed habitats, were found only in the spring-fed reach. The macroinvertebrate assemblage in the spring-fed reach was characterized by numerous burrowers, collector-gatherers, and crenobiont taxa, highlighting the contribution of these habitats to beta diversity in river networks.

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