Table 3 Summary of means, standard deviations (SD), sample numbers (N), mean mid-parental values (MPV) for thirteen morphological traits in C. aurita x Callithrix sp. hybrids (AH). In the “Mid-Parental Value (MPV)” columns “A_J” is the MPV between C. aurita and C. jacchus, “A_P” is the MPV between C. aurita and C. penicillata, and “A_G” is the MPV between C. aurita and C. geoffroyi. In the “P-values of t-Tests between MPV and Hybrid Means” columns “A_J x AH” represents p-values from t-tests between AH hybrid trait means to the A_J MPV, “A_G x AH” represents p-values from t-tests between AH hybrid trait means to the A_G MPV, and “A_P x AH" represents p-values from t-tests from AH hybrids to the A_P MPV. In the “P-values of t-Tests between Parental and Hybrid Means” column “AH-A” indicates p-values of Welch’s t-tests between AH hybrids and C. aurita trait means. The “AH-J” column indicates p-values of Welch’s t-tests between AH hybrids and C. jacchus trait means, the “AH-G” column indicates p-values of Welch’s t-tests between AH hybrids and C. geoffroyi, the “AH-P” column indicates p-values of Welch’s t-tests between AH hybrids and C. penicillata trait means. Significant p-values are indicated as “*” for p-value<0.05, as “**” for p-value<0.01, and as “***” for p-value<0.001. “Cm” refers to centimeters, “mm” to millimeters, and “g” to grams

BODY: Body length (cm)

9

21.4

1.9

20.9

21.4

22.0

0.488

0.307

0.946

0.433

0.056

0.327

0.534

C. aurita-like

FEMUR: Femur length (cm)

9

6.4

0.6

6.0

6.1

6.4

0.083

0.786

0.231

0.625

**

0.980

*

Intermediate between C. aurita and C. geoffroyi; Larger than C. jacchus and C. penicillata

FO: Fronto–Occipital Distance (mm)

9

38.8

3.6

41.1

41.2

41.4

0.094

0.064

0.083

*

0.538

0.326

0.433

Smaller than all putative parental species

FOOT: Foot Length(mm)

9

57.9

4.5

57.9

57.7

58.3

0.971

0.796

0.908

0.100

0.902

0.177

*

Intermediate between C. aurita and jacchus group species

FOREARM: Distance Wrist to Elbow (cm)

9

5.2

0.5

4.8

4.9

5.0

0.103

0.434

0.156

0.847

0.004

0.123

**

C. aurtia -like

HAND: Distance Wrist to Tip of Longest Finger (mm)

9

39.0

3.7

33.0

32.9

33.4

***

0.908

***

*

*

0.082

*

Transgressive relative to C. aurita and C. penicillata/C. jacchus

HUMERUS: Humerus Length (cm)

9

5.2

0.8

5.0

5.0

5.32

0.590

0.524

0.505

0.510

0.100

0.620

0.067

Intermediate between C. aurita and C. penicillata/C. jacchus

IC: Intercranial Distance (mm)

9

32.6

4.8

30.3

30.8

31.7

0.185

0.584

0.287

0.737

**

0.187

0.030

Intermediate between C. aurita and C. geoffroyi; Larger than C. jacchus and C. penicillata

JAW: Width of the Jaw (mm)

9

26.3

12.4

23.0

23.3

24.7

0.445

0.708

0.488

0.557

0.357

0.882

0.432

Larger than all putative parental species

TAIL: Tail Length (cm)

9

29.7

3.6

29.9

30.0

31.5

0.910

0.176

0.837

0.066

0.110

0.527

0.134

Intermediate between C. aurita and jacchus group species

TIBIA: Tibia Length (cm)

9

7.2

0.7

6.9

6.9

7.2

0.163

0.847

0.136

1.000

*

0.719

*

C. aurita-like

WEIGHT: Weight (g)

9

408.1

39.6

381.6

374.5

413.38

0.079

0.700

*

0.096

***

0.318

***

Heterotic relative to C. aurita and C. penicillata

ZYG: Maximal zygomatic breadth (mm)

9

30.3

3.0

30.1

30.0

30.8

0.808

0.665

0.756

0.355

0.157

0.886

0.129

Intermediate between C. aurita and jacchus group species