Table 1 Models explaining the coastal range (in km) occupied by non-native marine invertebrates.

From: Invasion Expansion: Time since introduction best predicts global ranges of marine invaders

Model ID

# variables

R2

AICc

ΔAICc

wi

Time since Introduction

Independent Variables

Biological

Physical

Habitat

Mobility

Max body size

Developmental type

Current speed (spring)

Current variability

Temperature mean (spring)

Temperature standard dev

Salinity mean

Salinity standard dev

Null

0

—

2643.4

38.9

4.7 × 10−10

           

A

4

0.29

2604.5

0.0

0.134

0.42

–0.19

 

0.15

     

−0.20

 

B

5

0.30

2605.3

0.8

0.090

0.42

–0.19

 

0.15

   

−0.08

 

–0.16

 

C

5

0.30

2605.6

1.1

0.078

0.41

–0.18

–0.08

0.14

     

–0.21

 

D

6

0.31

2605.7

1.2

0.073

0.40

–0.20

 

0.15

  

0.13

–0.17

 

–0.17

 

E

4

0.29

2605.9

1.4

0.068

0.45

–0.20

 

0.15

   

–0.15

   

F

5

0.30

2606.1

1.6

0.061

0.42

–0.19

 

0.14

–0.07

    

–0.20

 

G

5

0.30

2606.4

1.9

0.052

0.41

–0.20

 

0.16

  

0.05

  

–0.22

 

H

6

0.31

2606.6

2.1

0.047

0.41

–0.18

–0.08

0.13

   

–0.07

 

–0.17

 

I

7

0.32

2606.7

2.2

0.045

0.39

–0.18

–0.09

0.13

  

0.14

–0.16

 

–0.19

 

J

3

0.27

2606.8

2.3

0.042

0.41

–0.18

       

–0.21

 

K

6

0.31

2606.9

2.4

0.040

0.42

–0.19

 

0.13

–0.07

  

–0.08

 

–0.16

 

L

4

0.28

2606.9

2.4

0.040

0.40

–0.16

–0.11

      

–0.23

 

M

7

0.32

2607.0

2.4

0.040

0.40

–0.19

 

0.13

–0.08

 

0.14

–0.17

 

–0.18

 

N

4

0.28

2607.2

2.7

0.035

0.41

–0.18

     

–0.10

 

–0.16

 

O

7

0.32

2607.3

2.8

0.033

0.39

–0.20

 

0.15

 

–0.10

0.22

–0.19

 

–0.17

 

P

6

0.30

2607.3

2.8

0.033

0.40

–0.18

–0.09

0.14

  

0.06

  

–0.24

 

Q

7

0.31

2608.0

3.4

0.024

0.40

–0.20

 

0.15

  

0.13

–0.17

 

–0.16

0.02

R

3

0.26

2608.0

3.5

0.023

0.45

–0.19

     

–0.17

   

S

3

0.26

2608.9

4.4

0.015

0.46

–0.20

 

0.18

       

T

3

0.26

2609.2

4.6

0.013

0.39

 

0.15

      

–0.23

 

U

2

0.24

2610.7

6.2

0.006

0.40

        

–0.22

 

V

2

0.23

2611.8

7.3

0.004

0.44

      

–0.18

   

W

2

0.23

2612.2

7.7

0.003

0.45

–0.19

         

X

2

0.22

2613.6

9.1

0.001

0.45

  

0.16

       

Y

1

0.20

2616.0

11.4

0.0004

0.44

          

Z

1

0.09

2632.9

28.4

9.1 × 10–8

         

–0.30

 

AA

1

0.05

2638.7

34.2

5.1 × 10–9

       

–0.19

   

BB

1

0.02

2642.2

37.7

8.9 × 10−10

 

–0.16

         
     

RVI

1.00

1.00

0.26

0.83

0.18

0.08

0.28

0.55

0.08

0.84

0.12

  1. The four best fitting models are shown for each number of variables up to seven; with eight or more variables, models fit poorly (ΔAICc value > 3.7). The standardized beta coefficients associated with each independent variable are shown for each model (italics represent coefficients significant at P < 0.05 level). The best, most parsimonious model with the lowest Akaike information criterion (AICc) value is shown in bold. A null (intercept only) model is also compared. ΔAICc indicates the difference in model parsimony as explained by AICc relative to the best model; lower ΔAICc values indicate higher support for a model. Values of R2 and Akaike weight (wi) for each model are also shown. Akaike weights were calculated across the models shown in table. RVI (relative variable importance) is the sum of the weights (wi) of all models containing a particular parameter and were calculated across the best 40 models (lowest AICc). Habitat represents whether species is epifaunal or infaunal; mobility is sessile or mobile. Beta coefficients indicate that distributional extent decreases if habitat is epifaunal, and decreases for species that are mobile as adults.
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