Gan Wenjin EEPAI Group, XTBG How do spiders to be the Spiderman?

Gan Wenjin

EEPAI Group, XTBG

How do spiders to be the Spiderman?

The Superpower of Spiderman

Vision

(Lim & Daiqin Li, 2007)

(David Edwin Hill, 2010)(David Edwin Hill, 2010)

(Photographs by Ron Atkinson)

(Lim & Daiqin Li, 2007)

Silk

SCIENCEphotoLIBRARY

(Photographs by Ron Atkinson)

How spiders spin webs of great strength?

Stick thread

(Ron Atkinson)

What do spiders use their silk for?

Web

http://www.oocities.org/brisbane_spiders

Orb-web Frame Diagram

http://www.oocities.org/brisbane_spiders

Brain

Decoration-building Behavior

Web-decorating behavior

Spiral stabilimentum built by Cyclosa

spider

Cross-like stabilimentum spum by Argiope adults

Vertical-linear stabilimentum produced by other Argiope

species

Silk-decoration built by same species

(Photographs by Daiqin Li)

Forms of web decorations

(Herberstein et al. 2000)

Web decorations by Cyclosa sp.

Silk

Detritus

Egg sacs

Prey remains

Model system

WHAT…?

HOWWHY

Self-secreted materials(SS)

SilkEgg sacs Molt

Cyclosa octotuberculata

Collected materials(CO) Dry leaf

Green leaf

Prey remains BarkFlower pedals

Fibers

2 = 132.4, df = 2, P < 0.0001

Materials

Below 2% Discoid 5%

Linear 85%

Patterns

Above 8%

2 =385.2, df=3, P<0.0001

WHAT

HOW…?

WHY

Where Cyclosa spiders collect decorating materials to decorate their webs?

Experimental procedure

20 cm5 cm

20 cm

• Monitored the webs continuously for six days.

• Variables recorded:1. No. spiders decorating

webs.2. Mean No. pieces of paper

used.3. Mean decoration length.

0

10

20

30

40

Bottom Web Both Bottom Web Both

Adult Juvenile

Mea

n d

ecora

tion l

ength

(m

m)

Fig.1 Mean ( s.e.) cumulative decoration

length(mm) built by each experimental group of

spiders at the end of experiment in day5.

Results

0

20

40

60

80

100

Bottom Web Both Bottom Web Both

Adult Juvenile

% l

eaf

frag

emen

ts u

sed t

o

dec

ora

tion

Fig.2 Mean ( s.e.) cumulative number of dry-

leaf fragments used by each experimental group of

spiders to decorate their webs in day5.

WHAT

HOW…?

WHY

How Cyclosa spiders collect materials to decorate their webs?

Color

Texture

F3=2.417 P=0.70

F3=1.062 P=0.368

F3=1.686 P=0.174

• Fig.3 Number of different positions of different textures fragments of web decorations built by spiders in the day5.• Effect of different color fragments on the web and decoration traits in day5: F3 = 0.038, P=0.990 (ANOVA)

Texture

Weight

• Table 1 Effect of different weight fragments on the web and decoration traits in day5.

FactorWeb and decoration

traitsF 4 P

Weight CA 0.7930 0.5315TTL 0.8859 0.4741MH 0.1276 0.9722

Number of fragments 20.1639 <0.001

• Fig.4 Total number of spiders used 5 different weight fragments in day5.

WHAT

HOW

WHY…?

Fig. 5 Normalized reflectance spectra of Cyclosaoctotuberculata spiders, decorations and vegetation backgrounds

Plant detritus

A cost of web decoration: predator-attraction

The Super-organ of Spiders

Reference

• http://en.wikipedia.org/wiki/Spider

• http://www.oocities.org

• hhttp://www.arachnology.be/Arachnology.html

• http://www.findaspider.org.au

• Biology of Spiders, Folix, Oxford Express

• A Spider’s World: Senses and Behaviour, Barth, F.G., Springer-Verlag, Berlin

• Animal behavior (9th edition), John Alcock

Thank you!