Disclaimer: Please note that the data presented here is ...Magnitude of Genetic Bottlenecks Proportional Loss of Diversity in Introduced Populations % Heterozygosity Allelic Richness

Disclaimer:

Please note that the data presented here is preliminaryand subject to revision.

Founding Events in Invasions:genetic patterns & evolutionary consequences

Katrina Dlugosch • Ingrid ParkerUC Santa Cruz

Founder Effects on Genetic Diversity

Native Range

Native Range Invaded Range

Founder Effects on Genetic Diversity

Demographic bottlenecks = Genetic bottlenecks

Native Range

Introduction Growth Spread

Invaded Range

Founder Effects on Genetic Diversity

Founding Events in InvasionsOutline

Genetic patternsLiterature review: within-population diversity

How common are bottlenecks?Why/why not… multiple introductions?

Evolutionary consequencesHypericum canariense: single introductions

Quantitative trait evolution

Conservation Implications

Literature Review• Successful human-mediated introductions• Direct comparisons to source regions• No hybrids

Literature Review• Successful human-mediated introductions• Direct comparisons to source regions• No hybrids

• Nuclear markers: Expected Heterozygosity (H) , Allelic Richness (A)

• Per locus values averaged over loci and populations

Literature Review• Successful human-mediated introductions• Direct comparisons to source regions• No hybrids

• Nuclear markers: Expected Heterozygosity (H) , Allelic Richness (A)

• Per locus values averaged over loci and populations

Data from…62 species (58 studies)

13 Plants2 Fungi

48 Animals

Literature Review• Successful human-mediated introductions• Direct comparisons to source regions• No hybrids

• Nuclear markers: Expected Heterozygosity (H) , Allelic Richness (A)

• Per locus values averaged over loci and populations

Data from…62 species (58 studies)

13 Plants2 Fungi

48 Animals: 7 birds 1 reptile6 fish 2 amphibians 6 mammals 13 insects3 crustaceans 5 mollusks3 annelids 1 tunicate

Magnitude of Genetic Bottlenecks

Proportional Loss of Diversity in Introduced Populations[(introduced-source)/source]

Loss of diversityGain in diversity

-0.4 -0.2 0.2 0.4 0.6 0.8 1-0.6-0.8-10

5

10

15

20

25

30

35

40

% of Species

0

5

10

15

20

25

30

35

40

Magnitude of Genetic Bottlenecks

Proportional Loss of Diversity in Introduced Populations

%

Heterozygosity

Allelic Richness

Loss of diversityGain in diversity

-0.4 -0.2 0.2 0.4 0.6 0.8 1-0.6 1.2-1-1.4 -1.2

0

5

10

15

20

25

30

35

40

Magnitude of Genetic Bottlenecks

Proportional Loss of Diversity in Introduced Populations

%

Heterozygosity

Allelic Richness

Loss of diversityGain in diversity

-0.4 -0.2 0.2 0.4 0.6 0.8 1-0.6 1.2-1-1.4 -1.2

Bromustectorum

0

5

10

15

20

25

30

35

40

Magnitude of Genetic Bottlenecks

Proportional Loss of Diversity in Introduced Populations

%

Heterozygosity

Allelic Richness

Loss of diversityGain in diversity

-0.4 -0.2 0.2 0.4 0.6 0.8 1-0.6 1.2-1-1.4 -1.2

What determines diversity loss?

We examined:

• Historical evidence for multiple introductions

• Time since initial introduction

What determines diversity loss?

We examined:

• Historical evidence for multiple introductions

• Time since initial introduction

Single vs. Multiple Introductions

-1

-0.5

0

0.5

1

‘Single’ Multiple

Loss of Diversity

Prediction…

-1

-0.5

0

0.5

1

‘Single’ Multiple

Loss of A

-1

-0.5

0

0.5

1

Loss of He

‘Single’ Multiple

Single vs. Multiple Introductions

Reality…

What determines diversity loss?

We examined:

• Historical evidence for multiple introductions

• Time since initial introduction

Time Since Initial Introduction

-0.2

0

0.2

0.4

0.6

0.8

0 20 40 60 80 100 120 140 160

Years Since Initial Introduction

Loss of A

-0.2

0

0.2

0.4

0.6

0.8

0 20 40 60 80 100

Years Since Initial Introduction

Loss of A Multiple introductions / gene flowreplenish diversity over time

Time Since Initial IntroductionPrediction…

-0.2

0

0.2

0.4

0.6

0.8

0 20 40 60 80 100

Years Since Initial Introduction

Loss of A

Time Since Initial Introduction

Multiple introductions / gene flowreplenish diversity over time

Drift / directional selectionerode diversity over time

Prediction…

-0.2

0

0.2

0.4

0.6

0.8

0 20 40 60 80 100 120 140 160

Years Since Initial Introduction

Loss of A

Time Since Initial Introduction

Reality…

-0.2

0

0.2

0.4

0.6

0.8

0 20 40 60 80 100 120 140 160

Years Since Initial Introduction

Loss of A

P = 0.03r2 = 0.22

Time Since Initial Introduction

Founding Events in InvasionsOutline

Genetic patternsLiterature review: within-population diversity

Bottlenecks often occur during invasionBenefits of multiple introductions take time

Evolutionary consequencesHypericum canariense: single introductions

Quantitative trait evolution

Conservation Implications

Founding Events in InvasionsOutline

Genetic patternsLiterature review: within-population diversity

Bottlenecks often occur during invasionBenefits of multiple introductions take time

Evolutionary consequencesHypericum canariense: single introductions

Quantitative trait evolution

Conservation Implications

Hypericum canariense (Canary Island St. John’s wort)

Native Range: The Canary Islands

EL HIERRO

LA PALMA

LA GOMERA

TENERIFE

GRAN CANARIA

FUERTEVENTURA

LANZAROTE

3

21

3

1 2

12 3 4 5

66

5421

3

1

2 34 5

6

1213

14

78

9

1011 15

20 km

Native Range: The Canary Islands

EL HIERRO

LA PALMA

LA GOMERA

TENERIFE

GRAN CANARIA

FUERTEVENTURA

LANZAROTE

3

21

3

1 2

12 3 4 5

66

5421

3

1

2 34 5

67

8

9

1011

1213

1415

20 km

Native Range: The Canary Islands

Victoria

W. Australia

Maui

San Mateo Co.San Diego Co.

Single introductionsEach < 50 years old

H. canariense Invasions

H. canariense Invasions

H. canariense: San Mateo Co. California

0.00

0.05

0.10

0.15

0.20

0.25

Tenerife Populations Invasions

AFLP Variation (expected heterozygosity He)

0

5

10

15

20

25

30

35

40

Magnitude of Genetic Bottlenecks

Proportional Loss of Diversity in Introduced Populations

%

Heterozygosity

Allelic Richness

Loss of diversityGain in diversity

-0.4 -0.2 0.2 0.4 0.6 0.8 1-0.6 1.2-1-1.4 -1.2

Quantitative Trait Evolution

150

175

200

225

250

Tenerife Maui SD SM

***

Flowering Date (Julian day)

Native

Invading

*** P < 0.001

day

Flowering Date (Julian day)

175

200

225

250

20 25 30 35 40

NativeInvading

LATITUDE (degrees N)

InvasionsP = 0.002r2

adj = 0.30FamilyMeanDate

0

5

10

15

20

25

30

35

40

Magnitude of Genetic Bottlenecks

Proportional Loss of Diversity in Introduced Populations

%

Heterozygosity

Allelic Richness

Loss of diversityGain in diversity

-0.4 -0.2 0.2 0.4 0.6 0.8 1-0.6 1.2-1-1.4 -1.2

0

5

10

15

20

25

30

35

40

Magnitude of Genetic Bottlenecks

Proportional Loss of Diversity in Introduced Populations

%

Heterozygosity

Allelic Richness

Loss of diversityGain in diversity

-0.4 -0.2 0.2 0.4 0.6 0.8 1-0.6 1.2-1-1.4 -1.2

Quantitative Trait Evolution

• Latitudinal cline in phenology

• Higher growth rates

• Loss of inbreeding depression

Founding Events in InvasionsOutline

Genetic patternsLiterature review: within-population diversity

Bottlenecks often occur during invasionBenefits of multiple introductions take time

Evolutionary consequencesHypericum canariense: single introductions

Rapid evolution of quantitative traits

Conservation Implications

Founding Events in InvasionsOutline

Genetic patternsLiterature review: within-population diversity

Bottlenecks often occur during invasionBenefits of multiple introductions take time

Evolutionary consequencesHypericum canariense: single introductions

Rapid evolution of quantitative traits

Conservation Implications

Conservation Implications

Invaders do experience bottlenecks

Conservation Implications

Invaders do experience bottlenecks

BUT quantitative traits retainadaptive potential

Conservation Implications

Need early detection and eradication infrastructure for isolated populations

BUT quantitative traits retainadaptive potential

Invaders do experience bottlenecks

Acknowledgements

FundingUSDACA Native Plant SocietySTEPS Institute

ConversationExtended Parker LabGrant PogsonEllen SimmsJohn Thompson

InvitationTom Smith &Louis Bernatchez

Hypericum projectChris Bella, Pat Bily, Meghan Bishop, Mike Bonsall, Emme Bruns, Alex Bullis, Sara Crockett, Adrian Deveny, Jessica Grice, David Hamburger, Adrianne Haynes, Cynthia Hays, Kendra Hauser-Seaman, Chris Heintzelman, Beth Howard, Becky Hufft Kao, Andrea Jani, George Katibah, Nell Kolden, Jeremy Mason-Herr, Warren McCord, Justin Melhaff, Ian Miller, Ari Miller-Rhoads, Sara Mora, Raquel Paniagua, Neil Petersen, David Pivorunas, Mary Platter-Reiger, Fahim Popalzai, Ann Rich, James Richardson, Tzong Tzu Rogers, Will Satterthwaite, Annie Shattuck, Kate Siegfried, Jim Sowerwine, Kim and Forrest Starr, Jodi Stewart, Ryan Taylor, Erin Tempero, Jim Velzy, John Wade, Rebekah Weber, Emily Williams, Ryan Wilson, Nick Wolf, Peter Zee.