Evolutionary Biology and Practical Conservation: Bridging a Widening Gap

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1 Evolutionary Biology and Practical Conservation: Bridging a Widening Gap Georgina Mace Andy Purvis Evolutionary Change in human-altered environments UCLA

2 Outline The widening gap(s) Between the rate of environmental change and biodiversity loss, and our ability to mitigate it (>massive evolutionary change). Between what we could do to incorporate evolutionary processes into planning and management, and what we do in practice. Removing obstacles Better interfaces between science and policy

During 1950-2000 ecosystem change was more rapid than

cropland in the 30 years since 1950 than in the 150

reefs were lost and 20% degraded Flows of biologically

3 During ecosystem change was more rapid than any time in human history More land was converted to cropland in the 30 years since 1950 than in the 150 years between 1700 and % of the world s coral reefs were lost and 20% degraded Flows of biologically available nitrogen doubled and flows of phosphorus tripled

Species extinction rates are increasing Humans have increased the species extinction rate by as much as 1,000 times over background rates typical

4 Species extinction rates are increasing Humans have increased the species extinction rate by as much as 1,000 times over background rates typical over the planet s history Future projections suggest that species extinction rates could increase to 10 to 100 times higher than in the recent past.

5 The conservation status of threatened species is deteriorating Threatened birds show deterioration in their conservation status

6 On average local populations are declining According to the Living Planet Index, average population sizes declined by 30% between 1970 and 2003 Most animal groups surveyed in Europe showed declines in population of over 20% between 1980 to 2002

7 Ecosystem forest fragmentation Estimates of forest fragmentation due to anthropogenic causes. (Wade, T. G., K. H. Riitters, J. D. Wickham, and K. B. Jones Distribution and causes of global forest fragmentation. Conservation Ecology 7(2): 7. [online] URL:

Conversion of natural ecosystems is continuing, especially in biodiverse biomes More than two thirds of the area of two biomes and more than half of the area of four

8 Conversion of natural ecosystems is continuing, especially in biodiverse biomes More than two thirds of the area of two biomes and more than half of the area of four others had been converted by 1990 Projected future changes are concentrated in the tropics, while limited recovery is expected in the temperate forests and woodlands.

9 The distribution of species on Earth is becoming more homogenous Growth in Number of Marine Species Introductions in North America and Europe

10 Direct drivers of biodiversity loss are still growing in intensity Most direct drivers of degradation remain constant or are growing in intensity in most ecosystems

11 Strong directed selection from drivers Habitat change (loss of habitat specialists, evolution for reduced dispersal, patch extinction) Climate change (unpredictable effects from biotic mixing and new environments) Invasive species (novel threats massive effects, but also evidence for evolutionary responses) Over-exploitation (life history evolutionary responses) Pollution -including N, P loading (toxic blooms, simpler communities)

12 Consequences.? Biodiversity Is Both a Response Variable Affected by Global Change Drivers and a Factor That Affects Human Well-Being Figure from Diaz et al PLoS Biology (2006)

Species extinctions are affecting some taxa and ecological types disproportionately In many taxa, vulnerability to local extinctions is associated with: low abundance high habitat

13 Species extinctions are affecting some taxa and ecological types disproportionately In many taxa, vulnerability to local extinctions is associated with: low abundance high habitat specificity, large body size slow reproductive rates. In mammals and fishes, carnivores and high trophic level feeders. Fisher & Owens 2004; Dulvy et al., Cardillo et al., 2004; Purvis et al., 2000;

14 Extinction leads to loss of evolutionary history Phylogenetic branch length = evolutionary history Phylogenies are very resistant to random loss of species The internal branches (blue and red) can only be lost if all descendant species go extinct - they have insurance Orang Gorilla Humans Millions of years Chimp Bonobo

15 Extinction and evolutionary history Take a phylogeny (this one is a made-up one) Wipe out species at random See how loss of evolutionary history scales with loss of species Nee and May (1997) did this

16 Extinction and evolutionary history Wipe out half the species Only lose one internal branch Can lose most of the species and keep nearly all of the tree! e.g., lose 95% of species, keep 81% of branch length But it is worse because of correlations within clades

Evolutionary history and evolutionary process Random extinction Extinction probability positively correlated with speciation rate - lose short branches first

17 Evolutionary history and evolutionary process Random extinction Extinction probability positively correlated with speciation rate - lose short branches first Mooers & Heard 2000 Proc R Soc Extinction probability negatively correlated with speciation rate - lose long branches first Why are plants and animals different?

Overall loss of diversity (species, communities, ecosystems, functions and processes)

18 Summary: Anthropogenic impacts on current and future evolution Impacts are just about everywhere Strongly directed selection from main anthropogenic drivers (and a major new one climate change) Overall loss of diversity (species, communities, ecosystems, functions and processes) Homogenisation Selective loss Loss of natural disturbance regimes Loss of ecological complexity, linkages

19 ..leading to Failure of some ecosystem functions and services Increased risk of unexpected major changes, irreversible changes in state Protection from natural disasters New threats (emerging infectious diseases, climate change, nutrient loading) Millennium Ecosystem Assessment 2005

20 Current rates of environmental change and biodiversity loss- implications for future evolution? Myers and Knoll (2001) (PNAS) concluded that current patterns of biotic change will disrupt and deplete certain basic processes of evolution, with consequences likely to persist for millions of years. Distinctive features of future evolution could include a homogenization of biotas, a proliferation of opportunistic species, a pest-andweed ecology, an outburst of speciation among taxa that prosper in human-dominated ecosystems, a decline of biodisparity, an end to the speciation of large vertebrates, the depletion of "evolutionary powerhouses" in the tropics, and unpredictable emergent novelties.

21 How can we do better - from an evolutionary perspective? Setting goals Assessing status and trends Setting priorities for conservation and management Species recovery and management plans

22 Incorporating evolutionary processes into planning and management 1. Setting goals for environmental management and conservation Setting goals is important if you don t plan for where you want to get to, you ll end up somewhere else

23 The global 2010 target In April 2002, at the Sixth Conference of the Parties of the Convention on Biological Diversity (CBD) 123 Ministers committed themselves to actions to:.. achieve, by 2010, a significant reduction of the current rate of biodiversity loss at the global, regional and national levels as a contribution to poverty alleviation and to the benefit of all life on earth (Decision VI/26).

24 What is the 2010 target? to achieve, by 2010, a significant reduction of the current rate of biodiversity loss at the global, regional and national levels a) Measure of state, e.g. protected area coverage, species population size Declining at constant rate Declining at increasing rate Declining at decreasing rate

25 The indicators for the 2010 Biodiversity target Status and trends of components of biodiversity Sustainable use Sustainable use Threats to biodiversity Ecosystem integrity and Threats to biodiversity ecological goods and services Status of traditional knowledge Marine trophic index Benefit sharing Resources

26 What about conservation and environmental organisations? Setting goals for environmental management and conservation: the targets from 13 organisations from Redford et al Conservation Biology African Wildlife Foundation (AWF) 2. BirdLife International 3. Conservation International (CI) 4. English Nature 5. European Commission (Environment Directorate General) 6. Convention on Biological Diversity (CBD) 7. The Nature Conservancy (TNC) 8. Ramsar Convention 9. United States Forest Service (USFS) 10. Wildlife Conservation Society (WCS) 11.World Wide Fund for Nature Int'l / IUCN Joint Forest Policy Unit 12.World Wildlife Fund - US (WWF-US) 13.World Resources Institute (WRI)

27 Endemic Bird Areas (3) Range-wide Priority-Setting (16) Hotspots (4) Landscape Species (17) Major Tropical Wilderness Areas (5) 1. Setting goals for environmental management and conservation Natura 2000 (9) Last Wild Places (15) Ecoregional Conservation Planning (11) Heartland Selection (1) Site Conservation Planning (12) Biodiversity Visions (20) Natural Areas (5) Designing Sustainable Landscapes (4) Global 200 (17) Frontier Forests (18) Wetlands of International Importance (11) Figure from Redford et al Biodiversity Action Plans (6) Conservation Biology 2003 Ecosystem Approach (8) Lanscape Approach (16) Land and Resource Mangement Planning (12) species-some species-all communities ecol. process evol. process ecosystems- some ecosystems- all biodiversity natural features sustainable use equitable sharing people Target

28 2. Assessing the status and trends of biodiversity Measures of state, almost exclusively of areas, species and populations No measures of process (ecological or evolutionary) No measures of evolution or adaptability An important problem Possibilities: Using phylogenies loss of PD (branch length) in declining populations or species Direct monitoring of trends over time in genetic variation in populations Direct measures of evolutionary changes from traits

29 3. Setting priorities for conservation Area based planning 1. Systematic conservation planning many criteria can be included, but also usually species (sometimes with phylogenetic information). 2. Systematic conservation planning with ecological and evolutionary processes in mind

30 Does species-richness serve as a good surrogate for PD? Rodrigues rules Rodrigues et al. (2005) showed that PD scores would differ from species richness only if four conditions are all met: 1. Phylogenies must be unbalanced rather than symmetrical, 2. Closely-related species should tend to be found near to each other, 3. Old species must have smaller geographic distributions on average than young species, and 4. Old species must be found in species-poor areas Rodrigues et al., 2005

31 Mammals of Madagascar Grenyer et al., in prep.

32 Mammals of Madagascar Rodrigues rules? 1. Phylogeny unbalanced? 2. Phylogeny reflects geography? 3. Old species narrowly distributed? 4. Old species in speciespoor areas? Grenyer et al., in prep.

33 Mammals of Madagascar Rodrigues rules? 1. Phylogeny unbalanced? Not significantly 2. Phylogeny reflects geography? No correlation 3. Old species narrowly distributed? Reverse is true 4. Old species in speciespoor areas? Reverse is true Grenyer et al., in prep.

34 Systematic conservation planning with ecological and evolutionary processes in mind Cape Floristic Region Cowling and Pressey 2001 identified key evolutionary processes to be conserved, (as well as pattern from complementarity analysis) Ecological diversification of plant lineages in relation to fine-scale edaphic gradients Migration and exchange between inland and coastal biotas Ecological diversification of plant and animal lineages in relation to steep environmental gradients Geographical diversification of plant and animal lineages in relation to macroclimatic gradients Maintenance of all evolutionary processes, including predator prey processes involving top predators Exchange between phylogenetically distinct biotas. For each process identified necessary spatial component.

35 (A) juxtaposed edaphically different habitats; (B) entire sand movement corridors; (C) whole riverine corridors; (D) upland lowland gradients; (E) macroclimatic gradients; F) mega wilderness areas; (G) major biological transitions not identified in stages A F (H) an additional minimum set of areas required to achieve all pattern targets

36 4. Developing species recovery plans 1. Identification of appropriate units at the species level and below 2. Building adaptation into recovery plans

37 Identification of appropriate sub-units A phylogenetic species Cicindela dorsalis

38 A phylogenetic species Under PSC, any population fixed for a character not found elsewhere, is a species Sequence two genes - ITS 1 and cytochrome oxidase III - and look for such characters

39 A phylogenetic species Under PSC, any population fixed for a character not found elsewhere, is a species The Martha s Vineyard population has a G at position 5016 of the cytochrome oxidase III gene, and everyone else has an A - hooray! Vogler & DeSalle 1994 Mol. Biol. Evol.

40 Avise 2005

41 Top 20% of sites for endemic bird richness under BSC Islands not high priority

42 and under PSC Islands are now very high priority Petersen & Navarro-Siguenza 1999 Cons Biol

43 Identification of appropriate sub-units Confusion over identification of species and criteria for sub-units Species as units for legislation and planning Management units will vary depending on What is the goal for the species? What does it require? How is that best achieved?

44 Building adaptation and evolutionary change into species management plans Small scale examples only

45 Conclusions on incorporating evolutionary processes into planning and management There are (some) methods and techniques available now, but there is a long way to go at many levels and we are slipping further behind What should we do?

46 Towards better integration of evolutionary science to policy: reducing the obstacles 1. Establish a clear relationship between scientists and policy-makers. Scientist Policy maker FOCUS Free ranging Needs answers to specific issues STYLE LEGACY ROLE Innovation is a measure of success Idea, not the consequences Provide policy-relevant information Risk averse; avoid costly errors Consequences, not the idea Make decisions, incorporate other factors

47 Towards better integration of evolutionary science to policy: reducing the obstacles 1. Establish a clear relationship between scientists and policy-makers. 2. Conservation planning requires joint working by scientists and decision makers from beginning to end. 3. Conservation planning needs new tools and approaches, from evolutionary biologists and other disciplines. 1. Setting the right goals 2. Developing efficient plans at appropriate scales local versus regional. Optimising allocation of resources future vs. present. 3. Dealing explicitly with uncertainty, balancing major risks with achieving success. 4. Integrate to other societal goals

48 Towards better integration of evolutionary science to policy: reducing the obstacles 1. Establish a clear relationship between scientists and policy-makers. 2. Conservation planning requires joint working by scientists and decision makers from beginning to end. 3. Provide the right incentives for scientists and policy-makers to work together. 4. Provide the right incentives on both sides

49 Henk Wallays The End

by 2010 or beyond and what are the implications for the Convention on Biological Diversity?

6. What are the prospects for reducing the rate of loss of biodiversity by 2010 or beyond and what are the implications for the Convention on Biological Diversity? Biodiversity will continue to decline