Ecological ArchivesE087-191-A5

Sabrina E. Russo, Stephen Portnoy, and Carol K. Augspurger. 2006. Incorporating animal behavior into seed dispersal models: implications for seed shadows. Ecology 87:3160–3174.

Appendix E. Summary of parameter estimates, negative log-likelihood score and Akaike’s Information Criterion (AIC) for dispersal kernels fit to the simulated seed dispersal curve for each source tree.

Kernel

Parameter 1

Parameter 2

-L

AIC

Source tree 3

Exponential

0.01

NA

26985

53972

Gaussian

106.51

200.05

31981

63966

Lognormal

3.06

1.87

24321

48646

2Dt

0.26

12.37

23980

47964

Cauchy

5.83

4.45

27175

54354

Weibull

0.54

56.50

24785

49574

Source tree 4

Exponential

0.01

NA

1196

2394

Gaussian

112.31

201.08

1405

2814

Lognormal

3.13

1.86

1080

2164

2Dt

0.26

14.23

1061

2126

Cauchy

5.71

4.51

1206

2416

Weibull

0.54

60.10

1101

2206

Source tree 5

Exponential

0.01

NA

12226

24454

Gaussian

141.51

233.20

14113

28230

Lognormal

3.26

2.09

11134

22272

2Dt

0.21

7.87

11096

22196

Cauchy

5.03

7.07

12931

25866

Weibull

0.52

75.35

11236

22476

Source tree 6

Exponential

0.01

NA

2204

4410

Gaussian

110.85

221.55

2632

5268

Lognormal

3.01

1.99

1974

3952

2Dt

0.22

5.72

1967

3938

Cauchy

4.96

8.82

2288

4580

Weibull

0.52

55.97

2003

4010

Source tree 7

Exponential

0.01

NA

14525

29052

Gaussian

142.65

242.86

16843

33690

Lognormal

3.48

1.92

13520

27044

2Dt

0.22

14.06

13549

27102

Cauchy

15.86

35.19

15569

31142

Weibull

0.56

85.07

13634

27272

Source tree 8

Exponential

0.01

NA

1780

3562

Gaussian

185.64

267.02

2004

4012

Lognormal

3.58

2.29

1667

3338

2Dt

0.16

3.59

1690

3384

Cauchy

62.86

96.37

1945

3894

Weibull

0.53

109.16

1662

3328

Source tree 11

Exponential

0.01

NA

72930

145862

Gaussian

149.96

244.48

83945

167894

Lognormal

3.55

1.90

68065

136134

2Dt

0.23

20.96

68360

136724

Cauchy

11.29

19.52

77394

154792

Weibull

0.57

90.47

68650

137304

Source tree 12

Exponential

0.01

NA

2208

4418

Gaussian

150.88

220.28

2501

5006

Lognormal

3.62

2.06

2112

4228

2Dt

0.18

7.38

2155

4314

Cauchy

49.31

76.82

2417

4838

Weibull

0.59

100.42

2104

4212

Source tree 13

Exponential

0.01

NA

13679

27360

Gaussian

175.49

258.86

15471

30946

Lognormal

3.66

2.19

13002

26008

2Dt

0.16

4.04

13311

26626

Cauchy

67.99

81.90

14769

29542

Weibull

0.56

110.75

12926

25856

Source tree 16

Exponential

0.01

NA

13474

26950

Gaussian

180.41

263.23

15208

30420

Lognormal

3.82

2.05

12949

25902

2Dt

0.17

7.93

13294

26592

Cauchy

53.71

74.69

14538

29080

Weibull

0.59

121.23

12880

25764

Source tree 17

Exponential

0.01

NA

11543

23088

Gaussian

174.05

232.49

12871

25746

Lognormal

4.05

1.83

11379

22762

2Dt

0.20

28.51

11744

23492

Cauchy

90.44

80.60

12395

24794

Weibull

0.68

135.86

11283

22570

Source tree 19

Exponential

0.005

NA

14724

29450

Gaussian

215.805

290.679

16380

32764

Lognormal

4.207

1.821

14378

28760

2Dt

0.23

90.33

14782

29568

Cauchy

64.569

90.097

15888

31780

Weibull

0.656

160.703

14324

28652

All seeds

Exponential

0.01

NA

191929

383860

Gaussian

150.43

238.13

219991

439986

Lognormal

3.56

1.96

180254

360512

2Dt

0.21

14.14

181958

363920

Cauchy

14.58

31.77

206888

413780

Weibull

0.57

92.75

181105

362214

   Notes: Summary of parameter estimates, negative log-likelihood score (-L), and Akaike’s Information Criterion (AIC) for dispersal kernels fit to the simulated seed dispersal curve for each source tree with > 200 seeds and for all seeds from all 19 source trees. Source tree numbers correspond to those in Appendix A. Dispersal kernels for all seeds are plotted in Fig. 5a. Boldface indicates the kernel with the lowest AIC; however, the 8-parameter mixture distribution always had a lower AIC than best-fitting single-distribution dispersal kernel (Appendix F). Parameters one and two (respectively) for each kernel are: exponential, ; Gaussian, and ; Lognormal, and ; 2Dt, p and s; Cauchy, and s; Weibull, p and s (Appendix C).



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