Search

Alexander von Humboldt was arguably the most influential scientist of his day. Although his fame has since lessened relative to some of his contemporaries, we argue that his influence remains strong—mainly because his approach to science inspired others and was instrumental in furthering other scientific disciplines (such as evolution, through Darwin, and conservation science, through Muir)—and that he changed the way that large areas of science are done and communicated. Indeed, he has been called the father of a range of fields, including environmental science, earth system science, plant geography, ecology and conservation. His approach was characterized by making connections between non‐living and living nature (including humans), based on interdisciplinary thinking and informed by large amounts of data from systematic, accurate measurements in a geographical framework. Although his approach largely lacked an evolutionary perspective, he was fundamental to creating the circumstances for Darwin and Wallace to advance evolutionary science. He devoted considerable effort illustrating, communicating and popularizing science, centred on the excitement of pure science. In biogeography, his influence remains strong, including in relating climate to species distributions (e.g. biomes and latitudinal and elevational gradients) and in the use of remote sensing and species distribution modelling in macroecology. However, some key aspects of his approach have faded, particularly as science fragmented into specific disciplines and became more reductionist. We argue that asking questions in a more Humboldtian way is important for addressing current global challenges. This is well‐exemplified by researching links between geodiversity and biodiversity. Progress on this can be made by (a) systematic data collection to improve our knowledge of biodiversity and geodiversity around the world; (b) improving our understanding of the linkages between biodiversity and geodiversity; and (c) developing our understanding of the interactions of geological, biological, ecological, environmental and evolutionary processes in biogeography. [ABSTRACT FROM AUTHOR]

Aim: The links between geo‐ and biodiversity, postulated by Humboldt, can now be made quantitative. Species are adapted to their environments and interact with their environments by having pertinent functional traits. We aim to improve global ecometric models using functional traits for estimating palaeoclimate and apply models to Pleistocene fauna for palaeoclimate interpretation. Location: Global at present day, Pleistocene of Europe for fossil data analysis. Taxa: Artiodactyla, Perissodactyla, Proboscidea and Primates. Methods: We quantify functional traits of large mammal communities and develop statistical models linking trait distributions to local climate at present day. We apply these models to the fossil record, survey functional traits, and quantitatively estimate climates of the past. This approach to analysing functional relationships between faunal communities and their environments is called ecometrics. Results and main conclusions: Here, we present new global ecometric models for estimating mean annual and minimum temperature from dental traits of present day mammalian communities. We also present refined models for predicting net primary productivity. Using dental ecometric models, we produce palaeoclimate estimates for 50 Pleistocene fossil localities in Europe and show that the estimates are consistent with trends derived from other proxies, especially for minimum temperatures, which we hypothesize to be ecologically limiting. Our new temperature models allow us to trace the distribution of freezing and non‐freezing ecosystems in the recent past, opening new perspectives on the evolution of cold‐adaptive biota as the Pleistocene cooling progressed. [ABSTRACT FROM AUTHOR]

Abstract: Aim: We review the works of three pre‐Darwinian authors—Alexander von Humboldt, Augustin de Candolle and Alphonse de Candolle. Contrary to what other historiographers have claimed, we think that their works were not merely descriptive, nor did they adhere strictly to the inductivist model. Furthermore, the patterns described by these authors are still being studied extensively in biogeography. Method: We analyse the main concepts provided by these authors on the spatial patterns of biodiversity, and discuss how they served to construct the conceptual framework of contemporary biogeography. Results: In the early 19th century, secular naturalists began postulating explanations supported by empirical evidence and based on physical causes. The studied authors were extremely cautious when proposing hypotheses, considering that any statement not based on empirical evidence was mere conjecture. When we analyse the way they developed explanations, it seems evident that they were rather closer to deductive thought than to the orthodox inductivist model. With the rise of Darwinian evolutionism, naturalists lost interest in the spatial patterns of life and began constructing dynamic models where dispersal of individual lineages from northern centres of origin was proposed to explain their current distribution. Paradoxically, even though the evolutionary paradigm soon proved its great explanatory power, it simultaneously promoted a large number of studies in which speculation prevailed. Main conclusions: Even though the practices and methods of current biogeography have changed substantially, the studied patterns are still the same: (1) geographical gradients of richness and biotic replacement, (2) spatial gradients of functional groups, (3) geographical variation of the phenotype, (4) geographical patterns of expansion‐differentiation of single lineages and (5) biogeographical homology. The studied authors not only described rigorously biogeographical patterns, but also proposed explanations about them and even sometimes tested them based on empirical evidence, going beyond the prevalent inductivist canon. [ABSTRACT FROM AUTHOR]

Tropical climates and the biodiversity associated with them have long interested natural historians. Alexander von Humboldt inspired a generation of scientists, such as Charles Darwin and Alfred Russel Wallace, to observe and study tropical ecosystems. More recently, the mid-20th century saw Theodosius Dobzhansky and Daniel Janzen lay the foundations for studying adaptation to tropical climates. Now in the 21st century, we are beginning to realize the threats posed by current and future climate change to tropical populations which, despite relatively low levels of projected warming for low-latitude regions, face potentially significant detrimental impacts. Building on the insights of researchers in decades and centuries past, improved understanding of tropical ecology, evolution and biogeography will help us to conceive how future global change will impact on biodiversity. [ABSTRACT FROM AUTHOR]