Arctic systems in the Quaternary: Ecological collision, faunal mosaics and the consequences of wobbling climate

Authors: Hoberg, Eric; COOK, JOSEPH - University Of New Mexico; AGOSTA, SALVATORE - Virginia Commonwealth University; BOEGER, W - Universidade Federal Do Parana; GALBREATH, KURT - Northern Michigan University; LAAKSONEN, SAULI - Helsinki University; KUTZ, SUSAN - University Of Calgary; BROOKS, DANIEL - Madrid Institute For Advanced Studies

Submitted to: Journal of Helminthology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/12/2016
Publication Date: 4/20/2017
Citation: Hoberg, E.P., Cook, J.A., Agosta, S.J., Boeger, W., Galbreath, K.E., Laaksonen, S., Kutz, S.J., Brooks, D.R. 2017. Arctic systems in the Quaternary: Ecological collision, faunal mosaics and the consequences of wobbling climate. Journal of Helminthology. doi: 10.1017/S0022149X17000347.

Interpretive Summary: Climate change driven by anthropogenic forcing has supplanted a history of episodic variation and is eliminating ecological barriers and constraints on development and distribution for pathogen transmission. Our historical perspective indicates that ecological collision in evolutionary and ecological time creates new conditions and redraws maps and an understanding of distributions for hosts, parasites and diseases. Emergence of diseases and unanticipated cascades can drive perturbations in terrestrial, marine and aquatic systems, directly influencing ecological integrity and sustainability in northern systems and globally. We explore complexity linked to climate oscillations and how episodic or recurrent processes interact with evolution, ecology and biogeography to determine the structure and complex mosaic that is the biosphere. Parasites and parasite-host assemblages, within an expansive environmental matrix determined by climate, are key components in a general explanatory paradigm for global biodiversity. We explore the intricacies of faunal assembly in the context of Quaternary timeframes of the past 2.6 million years, a period dominated by episodic shifts in climate initially through cooling trends during the late Pliocene and subsequently through dramatic and episodic alternation between glacial and interglacial stages. Climate drivers on a continuum from geological to contemporary time scales serve to determine the structure and distribution of complex biotas. Cycles within cycles are apparent, with drivers that are layered, multifactorial and complex, influencing the dynamics and duration of climate states and shifts in environmental structure on varying temporal and spatial scales in Earth history. Although climate oscillations have dominated the Quaternary, contemporary dynamics are driven by tipping points and shifting balances emerging from anthropogenic forcing and global warming leading to extensive disruption of ecological structure and fauna at high latitudes and globally. We outline a framework to explore interactions of episodic processes on faunal structure and assembly, the Stockholm Paradigm, which appropriately shifts the focus to complexity and contingency in explanations of diversity. Climate mediates distribution, continuity and persistence of ecologically permissive environments through episodes of perturbation and stability. Climate cascades further mediate the dynamics of faunal assembly and the structure of biodiverse systems over time, the potential for invasion/ geographic expansion and isolation/ diversification (and extinction) of complex biotas, and ultimately patterns of emergent disease from local landscape islands to continental and intercontinental scales. Conceptually this is an important and relevant model for policy makers in governments, national agencies and NGO's, and a range of scientists from disease ecology to conservation biology in addressing the outcomes of accelerating climate change and environmental perturbation.

Technical Abstract: Climate oscillations and episodic or recurrent processes interact with evolution, ecology and biogeography determining the structure and complex mosaic that is the biosphere. Parasites and parasite-host assemblages, within an expansive environmental matrix determined by climate, are key components in a general explanatory paradigm for global biodiversity. We explore the intricacies of faunal assembly in the context of Quaternary timeframes of the past 2.6 million years, a period dominated by episodic shifts in climate initially through cooling trends during the late Pliocene and subsequently through dramatic and episodic alternation between glacial and interglacial stages. Climate drivers on a continuum from geological to contemporary time scales serve to determine the structure and distribution of complex biotas. Cycles within cycles are apparent, with drivers that are layered, multifactorial and complex, influencing the dynamics and duration of climate states and shifts in environmental structure on varying temporal and spatial scales in Earth history. An understanding of the dynamics of high latitude systems, the history of the Beringian nexus (the intermittent land connection linking Eurasia and North America) and downstream patterns of diversity depend on explanations of complexity in biotic assembly and persistence. Although climate oscillations have dominated the Quaternary, contemporary dynamics are driven by tipping points and shifting balances emerging from anthropogenic forcing leading to extensive disruption of ecological structure and fauna at high latitudes and globally. A framework to explore interactions of episodic processes on faunal structure and assembly is the Stockholm Paradigm which appropriately shifts the focus from cospeciation to complexity and contingency in explanations of diversity. Climate change driven by anthropogenic forcing has supplanted a history of episodic variation and is eliminating ecological barriers and constraints on development and distribution for pathogen transmission.