class: center, middle, inverse, title-slide .title[ # 1. Introduction to Niche Theory ] .author[ ### Jasper Slingsby, BIO2014F ] .date[ ### 2024-04-19 ] --- <img src="images/seeds_front.jpg" width="75%" style="display: block; margin: auto;" /> --- <img src="images/seeds_back.jpg" width="75%" style="display: block; margin: auto;" /> --- <img src="images/seed_instructions.jpg" width="70%" style="display: block; margin: auto;" /> --- <img src="images/sabertooth.png" width="75%" style="display: block; margin: auto;" /> .footnote[image: Mauricio Antón, CC BY 3.0] --- class: center, middle This module is about **formalising scientific definitions for the niche** and exploring how **this allows us to develop theory** to help understand and predict various aspects of biodiversity. --- layout: false .pull-left[ ### Early observations of the Niche <img src="images/Willdenow.jpg" width="60%" style="display: block; margin: auto;" /> .footnote[image: Wikipedia] ####_Carl Ludwig Willdenow_, 1765-1812 ] .pull-right[ Perhaps the first to recognize the role of climate in determining the geography of plants, with vegetation organised in latitudinal and elevation zones. <img src="images/willdenowia_sulcata_AGR.jpg" width="100%" style="display: block; margin: auto;" /> .footnote[image: Tony Rebelo CC BY-SA 4.0] ####_Willdenowia sulcata_, The "Groovy Sunreed" or Sonkwasriet, Restionaceae ] --- layout: false .pull-left[ ### Early observations of the Niche <img src="images/von_Humboldt.jpg" width="50%" style="display: block; margin: auto;" /> .footnote[painting by: Joseph Karl Stieler, 1843] ####_Alexander von Humboldt_, 1769-1859 A friend of Willdenow, and first to test his ideas. ] .pull-right[ <img src="images/humboldt.jpg" width="80%" style="display: block; margin: auto;" /> .footnote[_Essay on the Geography of Plants_, von Humboldt and Bonpland (1805) documents repeated vegetation zones with elevation in the Andes.] ] --- background-image: url("images/torres_del_paine.jpg") background-size: contain --- layout: false ## Climate zones and biomes <img src="images/resolv_ecoregions2017.png" width="70%" style="display: block; margin: auto;" /> .footnote[https://ecoregions.appspot.com/] --- layout: false .pull-left[ ## Climate zones and biomes Here is RH Whittaker's mapping of biomes against two major axes of climate variation. He wasn't the first to do this, but the "Whittaker plot" is one of the best known. The biomes align reasonably well with temperature and precipitation. The biomes are largely defined by the dominant plant functional types. ] .pull-right[ <img src="images/whittakerplot.png" width="100%" style="display: block; margin: auto;" /> .footnote[[**Whittaker 1975**](https://search.worldcat.org/title/communities-and-ecosystems/oclc/1091611)] ] --- class: center, middle # Hang on? <img src="images/world_seasonality.gif" width="80%" style="display: block; margin: auto;" /> ### We started by talking about growing vegetables and now we're looking at the whole world? --- layout: false ## The Hierarchy of Ecology .left-column[ **Individual organism** **Populations** are groups of interacting individuals of the same species. **Communities** are groups of interacting individuals or populations of different species. **Ecosystems** are the combination of biotic communities and their physical environment. ] .right-column[ <img src="images/hierarchy_in_ecology.jpg" width="95%" style="display: block; margin: auto;" /> ] .center[image: _The Atlas of World Wildlife_ 1973] --- class: center, middle ## The Niche Concept and the Hierarchy of Ecology The Niche Concept is **typically applied at the level of species**, but has implications for higher order levels of the hierarchy - i.e. populations, communities, ecosystems (including biomes or the whole biosphere). > _"The niche concept is not always used explicitly in theories at all these levels of organization, but it provides an important, if sometimes implicit connection between these disparate fields of ecology that justifies its status as a fundamental ecological concept."_ - [**Leibold 1995**](http://dx.doi.org/10.2307/1938141) --- class: middle ## Take-home >*While the idea that species have particular environmental preferences/requirements and that they play specific roles in ecosystems is as old as life itself, the formal recognition and development of definitions of the niche allows us to develop more sophisticated theory in ecology and evolution.* >*Niche theory has its roots in early biogeographic observations about the geography of plants by Willdenow, von Humboldt and others.* >*While the niche concept has implications for other levels of the ecological hierarchy (populations, communities, ecosystems, biomes), it is typically applied at the level of species.* --- class: center, middle # Thanks! 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