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Following the Dynamics of Structural Variants in Experimentally Evolved Populations

Following the Dynamics of Structural Variants in Experimentally Evolved Populations

Published on: February 3, 2023

Harvested populations are more variable only in more variable environments.

Tom C Cameron¹, Daniel O'Sullivan², Alan Reynolds²

¹School of Biological Sciences University of Essex Colchester CO43SQ UK.

Ecology and Evolution

|August 13, 2016

Summary

This summary is machine-generated.

Selective harvesting impacts population variability, especially in variable environments. Harvesting adults increased population variability and reduced size in fluctuating food conditions, unlike stable environments.

Keywords:

Age‐truncation density dependence environment harvesting microcosm mortality population dynamics predation seasonality stage‐structure threshold variability

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Area of Science:

Ecology
Population Biology
Environmental Science

Background:

The interplay between environmental variability and population dynamics is crucial for managed species, especially with climate change.
Debates exist on whether exploitation or environmental variation most affects population stability, yield, and extinction risk.
Theoretical models suggest harvesting's effect on population variability depends on environmental conditions, necessitating empirical testing.

Purpose of the Study:

To investigate the interaction between selective harvesting and environmental variation in food availability.
To assess the impact on the variability of stage-structured invertebrate populations over 20 generations in experimental microcosms.

Main Methods:

Utilized an invertebrate model species in controlled experimental microcosms.
Manipulated food availability to create constant and variable environments.
Applied selective harvesting of adults, varying harvesting strategies (proportional, threshold) and environmental variation patterns (random, periodic).

Main Results:

In constant food environments, adult harvesting had minimal effect on population size or variability.
In variable food environments, adult harvesting significantly increased population variability and decreased population size.
The effect of harvesting on population variability was contingent on harvesting strategy, environmental variation pattern, and temporal dynamics.

Conclusions:

Predicting the population response to selective harvesting is highly sensitive to the demographic structure and emergent processes within varying environmental contexts.
Environmental variation can amplify the effects of harvesting on population dynamics, highlighting the need for context-specific management strategies.
This study underscores the importance of considering environmental fluctuations when assessing the impact of harvesting on population stability and sustainability.