A Comparison of Two Methods for Quantifying Remige Structure Galen Dolkas

Slater Museum of Natural History

Advisor: Peter Wimberger

Class Aves

Wings and Remiges

Primary Feathers

Secondary FeathersP1

P10

S1SP

Past Research

From Pap et al. 2015

From Bachmann et al. 2007

Order Strigiformes

Methods- Remige Measurements

y

y

Methods- Remige Measurements

y

y

Methods- Remige Measurements

Pythagorean Properties

Pythagorean Properties

Par BD= Perp BD * sin(BA)

0 10 20 30 40 50 60 70 80 900.0

1.0

2.0

3.0

4.0

5.0

6.0

Bubo virginianus

Barb Angle (°)

Bar

b De

nsity

(bar

bs/ m

m)

Outer vane parallel barb density ranges

Inner vane parallel barb density ranges

Perpendicular barb densities

0 10 20 30 40 50 60 70 80 900.0

1.0

2.0

3.0

4.0

5.0

6.0Bubo virginianus

Tyto alba

Barb Angle (°)

Bar

b De

nsity

(bar

bs/ m

m)

Outer vane parallel barb density ranges

Inner vane parallel barb density ranges

Perpendicular barb densities

-6 -4 -2 0 2 4 6

-3-2

-10

12

3

PC1 vs. PC2

PC1

PC

2

Forest

Forest EdgeGrassland

PCA of Habitat

Parallel Barb Density

-4 -2 0 2 4 6 8

-3-2

-10

1

PC1 vs. PC2

PC1

PC

2

Forest

Forest EdgeGrassland

Perpendicular Barb Density

-4 -2 0 2 4

-4-2

02

PC1 vs. PC2

PC1

PC

2

Forest

Forest Edge

Grassland

-4 -2 0 2 4 6 8

-3-2

-10

1

PC1 vs. PC2

PC1

PC

2

Forest

Forest EdgeGrassland

-4 -2 0 2 4

-4-2

02

PC1 vs. PC2

PC1

PC

2

Forest

Forest Edge

Grassland

Barb Angle

PCA of Foraging Strategy

Long Perch: Foraging at a perch, and waiting at each perchActive Flapping: Foraging requires actively flapping of wingsShort Perch: Foraging at a perch, then immediately flying to another perchSoaring: Foraging does not require active wing flapping

-6 -4 -2 0 2 4 6

-3-2

-10

12

3

PC1 vs. PC2

PC1

PC

2

Active FlappingLong Perch

Short PerchSoaring

-4 -2 0 2 4 6 8

-3-2

-10

1

PC1 vs. PC2

PC1

PC

2

Active Flapping

Long Perch

Short Perch

Soaring

-4 -2 0 2 4

-4-2

02

PC1 vs. PC2

PC1

PC

2

Active Flapping

Long Perch

Short Perch

Soaring

Parallel Barb Density Perpendicular Barb Density Barb Angle

Future Research

0 500 1000 1500 2000 2500 30000.0

2.0

4.0

6.0

8.0

10.0

12.0

f(x) = 14.5730408655781 x^-0.188813069172804R² = 0.426174408322631

Bird Mass

P10

Out

er V

ane

Perp

Bar

b De

nsity

Acknowledgements

– Peter Wimberger for his tireless help and advice

– The Slater and Burke Museums for use of their collections

– The Slater staff for their advice and support

– Peter Hodum and Carrie Woods for answering all my stats questions

– ΦΣ, for putting on this symposium

– You, for coming to this symposium

Questions?

Bubo virginianus Remiges

10 20 30 40 50 60 70 80 900.00.51.01.52.02.53.03.54.04.5

Barb Angle

Barb

Den

sity

10 20 30 40 50 60 70 80 900.00.51.01.52.02.53.03.54.04.5

Barb Angle

Barb

Den

sity

10 20 30 40 50 60 70 80 900.00.51.01.52.02.53.03.54.04.5

Outer Vane

Inner Vane

Outer Vane

Inner VaneBarb Angle

Barb

Den

sity

10 20 30 40 50 60 70 80 900.00.51.01.52.02.53.03.5

Barb Angle

Barb

Den

sity

P10P1

S1 SP