The Spatial & Temporal Constraint Component of β diversity: here, there, & everywhere

1. The Spatial & Temporal ConstraintComponent ofβ diversity: here, there, & everywhere • Part 1: An introduction to βdiversity • Scale: grain & extent • What is β diversity? • The Two Pillars and Two Components of β diversity • Niche difference or Gradient β • Spatial & Temporal Constraint β • Part 2: Examples of Spatial & Temporal Constraint βdiversity at large scales • Diversity in North Temperate forests • Narrow endemism in eastern North America

2. α,β,γ,δ diversity • Most famous from the papers of Whittaker and MacArthur in the 1960s • As we will see, β is different than the others • And these 4 Greek symbols represent just two concepts: • Inventory Diversity • Differentiation diversity

3. Scale: Grain & Extent

4. Scale: Grain & Extent Grain: α,γ,δ Extent: β

5. Scale: Grain & Extent For nested samples, Extent incr. with grain by way of the Pythagorean Theorem Extent/area sampled: 1.4/1, 4.2/9, 7.1/25 2/2, 3/2, 5/2 Grain: α,γ,δ Extent: β

6. Scale: Grain & Extent For nested samples, Extent incr. with grain by way of the Pythagorean Theorem Extent/area sampled: 1.4/1, 4.2/9, 7.1/25 2/2, 3/2, 5/2 Many estimates of spp-grain (area) relation; few of spp-extent relation

7. Grain, extent, & sampling

8. 2 Kinds of Diversity Inventory Diversity α, γ, δ Differentiation Diversity β

9. 2 Kinds of Diversity Inventory Diversity α, γ, δ αCommunity Differentiation Diversity β

10. 2 Kinds of Diversity Inventory Diversity α, γ, δ αLandscape Differentiation Diversity β

11. 2 Kinds of Diversity Inventory Diversity α, γ, δ αRegion Differentiation Diversity β

12. 2 Kinds of Diversity Inventory Diversity α, γ, δ Differentiation Diversity β

13. 2 Kinds of Diversity Inventory Diversity α, γ, δ Differentiation Diversity βSmall Extent βLandscape βGradient

14. 2 Kinds of Diversity Inventory Diversity α, γ, δ Differentiation Diversity βLarge extent βRegion

15. β diversity measures • β= γ / α…and many others αγ

16. β diversity measures • β = γ / α…and many others • β = the distance decay of similarity Similarity = c / (a + b – c) and others The first law of geography: the similarity between two observations decreases or decays with distance Sd = S0 e-cd, d is distance, c is the rate of distance decay, S0 is the initial similarity a cb

17. The Two Pillars of Ecological Explanation The Niche Difference Model The Model of Spatial & Temporal Constraint

18. The Two Pillars of Ecological Explanation The Niche Difference Model: Niche differences, Environmental gradients, & disturbances explain distribution

19. The Two Pillars of Ecological Explanation The Model of Spatial & Temporal Constraint: Size & isolation of habitats implying also time explain distribution

20. The rate of distance decay, c, varies with Two traits of environment & Two traits of organisms: Environment Organismtraits AdaptationGradients Niche Movement Resistance Vagility

21. The rate of distance decay, c, varies with Two traits of environment & Two traits of organisms: Environment Organism traits AdaptationGradients Niche Movement Resistance Vagility

22. The rate of distance decay, c, varies with Two traits of environment & Two traits of organisms: Environment Organism traits Adaptation Gradients Niche MovementResistance Vagility Two relationships between organisms & environment: Adaptation & Movement Shortly: The Two Pillars of Ecological Explanation

23. The rate of distance decay, c, varies with Two traits of environment & Two traits of organisms: Environment Organism traits Adaptation Gradients Niche MovementResistance Vagility Two relationships between organisms & environment: Adaptation & Movement The Two Pillars of Ecological Explanation

24. Spatial extent & distance decay Extent correlates with similarity decay in two ways! The two components of beta diversity: As Distance Niche Difference Environmental similarity Spatial & Temporal Constraint Barriers to dispersal Time needed to saturate Similarity

25. 2 Kinds of Diversity Inventory Diversity α, γ, δ Differentiation Diversity β βGradient βSpatial & Temporal Constraint

26. Diversity patterns in North temperate forests Explanations of distribution The Niche Difference Model The Model of Spatial & Temporal Constraint

27. Explanations of species richness patterns 1st Pillar: Energy-Diversity Theory Species richness is self-limiting, in equilibrium with environment (energy availability), & convergent in similar environments (at similar energies).

28. Explanations of species richness patterns 1st Pillar: Energy-Diversity Theory Species richness is self-limiting, in equilibrium with environment (energy availability), & convergent in similar environments (at similar energies). All you need to know is current environment (energy availability)!

29. Energy-Diversity Theory AET > Latitude Currie & Paquin 1987 Nature 329, 326-327 Data only for North American trees at grain sizes of ca 2.5 degr Lat x 2.5 degr Long Tree Spp AET

30. Energy-Diversity Theory r2=.76 Residuals=Elevation, coastal proximity not climate variability or glacial history Currie & Paquin 1987 Nature 329, 326-327 Data only for North American trees at grain sizes of ca 2.5 degr Lat x 2.5 degr Long Tree Spp AET

31. Energy-Diversity Theory Currie & Paquin 1987 Nature 329, 326-327 The equation for No America predicts tree richness in Europe—no glacial extinctions need be invoked—but predictions often 10-20% off. Tree Spp AET

32. Explanations of species richness patterns 2nd Pillar: Historic Biogeography Species richness is a function of the constraints of time & space.

33. Explanations of species richness patterns 2nd Pillar: Historic Biogeography Species richness is a function of the constraints of time & space. Not predictable from current environment (unless environment and history are themselves correlated)!

34. The question of intercontinental convergence in similar environments: Temperate forests in East Asia & Eastern North America Japan

36. Acer From Ricklefs & Latham 1993 Quercus Prunus Crataegus Carpinus Sorbus Fraxinus Carya Populus Malus Alnus

38. Walnut Maakia Basswood Ash Elm Chestnut oak Red maple Mulberry Phelodendron Striped maple Cherry Sugar maple Elm Asian maples Silver maple Birch Holly Beech Poplar White pine Birch Hawthorn

39. Magnolia, Liriodendron Nyssa Carya Pachysandra Buckleya, Catalpa, Cladrastis, Epigaea, Gleditsia, Gymnocladus, Halesia, Itea, Menispermum, Mitchella, Pieris, Pyrularia, Sassafras, Wisteria Adlumia, Astilbe, Caulophyllum, Diphyleia, Hydrastis, Jeffersonia, Panax, Phryma, Podophyllum, Shortia, Tipularia

40. Supragenera: Calycanthus, Chimonanthus Subgenera: Striped maples

41. Magnolia, Nyssa

42. Fagus, Ostrya, Tilia Magnolia, Nyssa

43. Hamamelidaceae Fagus, Ostrya, Tilia Magnolia, Nyssa

44. Clintonia, Torreya, Tsuga, Trillium Hamamelidaceae Fagus, Ostrya, Tilia Magnolia, Nyssa

45. Acer, Cornus, Aesculus, Cercis Clintonia, Torreya, Tsuga, Trillium Hamamelidaceae Fagus, Ostrya, Tilia Magnolia, Nyssa

46. Acer, Cornus, Aesculus, Cercis Clintonia, Torreya, Tsuga, Trillium Hamamelidaceae Fagus, Ostrya, Tilia Magnolia, Nyssa

47. Acer, Cornus, Aesculus, Cercis Clintonia, Torreya, Tsuga, Trillium Hamamelidaceae Fagus, Ostrya, Tilia Magnolia, Nyssa In well-developed genera, E Asia=2x E No America

48. Diversity Patterns • The Challenges of Demonstrating a Diversity Anomaly: Scale Dependence & Environmental Differences • Empirical Results & Interpretation: • Ricklefs, Qian & White 2004 • Qian & White, unpublished • Qian, Ricklefs & White 2004 • Causes

49. Similar Environments, different richness: A Diversity Anomaly! EAsia>ENAmer 1.3-2x as many species! BUT these numbers depend on scale and range of latitudes!

50. Problem 1: Scale dependence!