Mountains, Climate and Biodiversity

Carina Hoorn, Allison Perrigo, Alexandre Antonelli, Carina Hoorn, Allison Perrigo, Alexandre Antonelli

• Publisher: Wiley-Blackwell
• Year: 2018
• ISBN:
  9781119159889
• Edition: 1
• Topic: Physical Sciences
• Subtopic: Geology & Earth Sciences

Mountains, Climate and Biodiversity: A comprehensive and up-to-date synthesis for students and researchers

Mountains are topographically complex formations that play a fundamental role in regional and continental-scale climates. They are also cradles to all major river systems and home to unique, and often highly biodiverse and threatened, ecosystems. But how do all these processes tie together to form the patterns of diversity we see today?

Written by leading researchers in the fields of geology, biology, climate, and geography, this book explores the relationship between mountain building and climate change, and how these processes shape biodiversity through time and space.

• In the first two sections, you will learn about the processes, theory, and methods connecting mountain building and biodiversity

• In the third section, you will read compelling examples from around the world exploring the links between mountains, climate and biodiversity

• Throughout the 31 peer-reviewed chapters, a non-technical style and synthetic illustrations make this book accessible to a wide audience

• A comprehensive glossary summarises the main concepts and terminology

Readership: Mountains, Climate and Biodiversity is intended for students and researchers in geosciences, biology and geography. It is specifically compiled for those who are interested in historical biogeography, biodiversity and conservation.

1
Mountains, Climate and Biodiversity: an Introduction

Carina Hoorn¹, Allison Perrigo^2,3,4 and Alexandre Antonelli^3,4,5

¹ Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Netherlands

² Forest Cat Editing, Uppsala, Sweden

³ Gothenburg Global Biodiversity Centre, Gothenburg, Sweden

⁴ Department of Biological and Environmental Sciences, University of Gothenburg, Gothenburg, Sweden

⁵ Gothenburg Botanical Garden, Gothenburg, Sweden

Abstract

Mountains harbor about one‐quarter of all terrestrial species in about a tenth of the world’s continental surface outside Antarctica. This disproportionate diversity makes mountains a focal point for research on the generation and maintenance of biodiversity. Some of the key features that make mountains so biologically diverse are the elevational gradient, physiographic and climatic diversity, and prolonged isolation of their peaks and valleys. These features reflect the complex interactions between plate tectonics and mountain building, climate change and erosion over time scales extending to millions of years. It is now widely accepted that these large‐scale processes play a fundamental role in biotic evolution across space and time. Together with ecological interactions among organisms, they form the basis for modern biogeography. But why, when and how the interactions between the geosphere, biosphere and atmosphere resulted in such high biodiversity in mountains is insufficiently understood. In this book, a multidisciplinary team of authors discusses the state of research at the interface between the geo‐ and biospheres and addresses these and other questions, while presenting examples from mountain systems around the world.

Keywords: mountain building, biodiversity, plate tectonics, geo‐biodiversity

1.1 Introduction

Can you imagine a world without mountains? It would undoubtedly be a much less diverse place in terms of biomes, habitats and species. Mountains are the cradles of all major river systems, they are the central determinants of regional‐ and continental‐scale climate and they comprise many unique biomes (Figure 1.1). They generate massive influxes of sediment that are divulged into adjacent territories (e.g., from the Andes across the Amazon basin, and from the Rockies into the Great Plains). For these reasons, the effects of mountains reach well beyond their immediate slopes (Gentry 1982; Finarelli & Badgley 2010; Hoorn et al. 2010).

Figure 1.1 The center section of Humboldt’s classical tableau, illustrating a cross‐section of the Chimborazo volcano in Ecuador, the highest mountain peak as measured from the center of the globe. This detailed drawing depicts one of the earliest studies of how the mountain biota is structured along an elevation gradient. Humboldt recognized the existence of distinct vegetation zones at different elevations with largely unique sets of species, constrained by climatic and physiological adaptations. This pioneering work is often considered a landmark in biogeography.

Source: Humboldt & Bonpland (1807). See also Plate 1 in color plate section.

Mountains also have a dual role in that they both generate and receive biodiversity (Hoorn et al. 2013). On one hand, they can generate diversity through in situ adaptations and diversification, subsequently providing neighboring regions with new lineages (e.g. Antonelli et al. 2009; Santos et al. 2009). On the other, they are able to support pre‐adapted lineages from other similar montane regions that arrive via long‐distance dispersal (Merckx et al. 2015). Nevertheless, teasing apart the relative contributions of in situ diversification versus dispersal (Antonelli 2015), and assessing how and when different climatic and geological conditions influenced different regions, is a matter of intense research. Likewise, we are just beginning to understand how and when climate and tectonism interact, and how they together affect biodiversity.

The effect mountain building has on climate, and how these processes together influence the speciation, extinction and migration of different taxa, is hotly debated. A number of studies have touched on some or many aspects of this set of interactions (Hughes & Atchison 2015; Hughes 2016; Lagomarsino et al. 2016), yet none has fully addressed the complexity of the field in a single work. We have therefore commissioned 31 peer‐reviewed chapters that, when taken as a whole, address this need.

One of the fundamental questions to address is: How can we untangle mountain building and climate change, and what influence did each of these processes have on biological diversification? It has been known for some time that Plio–Pleistocene climate change is responsible for pronounced changes in relief and a vast increase in global erosion rates (Molnar & England 1990). However, in recent years, mountain uplift, rates of erosion and paleoaltitude have begun to be measured more accurately, thanks to advances in analytical methods in geosciences (e.g., in the fields of isotope and fission‐track analysis) (Gosse & Stone 2001; McElwain 2004; Reiners & Brandon 2006; Forest 2007; Polissar et al. 2009; Lomax et al. 2012; Mulch 2016). These developments have enabled a global assessment of the timing and geographic extent of mountain building, erosion and relief (Herman et al. 2013; Herman & Champagnac 2015). Together, the data thus obtained provide a geohistorical guideline that helps to improve models of biotic evolution. Accurate mountain uplift ages have already been successfully applied in the context of molecular phylogenetic studies that test for the influence of surface uplift on species diversification (Lagomarsino et al. 2016).

Other major questions include: When did taxa evolve, how did they respond to the ecological opportunities that followed from mountain building and what were their geographic distributions through time? The generation of novel, carefully sampled biological data from extant species, together with improved databases on the fossil record – including enhanced geochronology from the Neotoma Paleoecology database, the Paleobiology database and Neclime, to name but a few –offers new perspectives on biotic evolution in mountain regions (e.g., Favre et al. 2015; Flantua et al. 2015). This, combined with new methods for predicting diversification and range evolution based on fossil records (e.g. Silvestro et al. 2016) and molecular sequences (e.g. Antonelli et al. 2016; Morlon et al. 2016) and methods for cleaning and processing vast amounts of extant species‐occurrence data (Töpel et al. 2016), provides researchers with valuable tools and data for testing specific hypotheses on the evolution of mountain biodiversity.

Finally, determining the relative roles of abiotic and biotic processes in the assembly, generation and maintenance of biodiversity is a central task in understanding biological distributions, and it forms the core of this book. Here, specialists from different disciplines have joined forces to synthesize the current knowledge on mountain building, climate and biodiversity. To help the reader through this cross‐disciplinary volume, the text is accompanied by a glossary of terms and a geological time scale (see back‐cover inset).

1.2 What are Mountains?

Mountains are defined as “landforms that rise prominently above their surroundings, generally exhibiting steep slopes, a relatively confined summit area, and considerable local relief” (Molnar 2015). They cover over a tenth of the continental surface of the Earth (Figure 1.2), based on a recent evaluation by Körner et al. (2016), who used the ruggedness of Earth’s terrestrial surface, excluding Antarctica, as the constraining...

Table of contents

• Cover
• Title Page
• Table of Contents
• List of contributors
• Acknowledgments
• Foreword
• Biography of Editors
• Glossary
• About the Companion Website
• 1 Mountains, Climate and Biodiversity: an Introduction
• Part I: Mountains, Relief and Climate
• Part II: When Biology Meets Mountain Building
• Part III: Mountains and Biota of the World
• Index
• End User License Agreement