Arthropods
Why So Successful?
Why So Abundant?
Why So Successful?
Why So Abundant?
Fact:
There are more than 1 million different
species of arthropod
Fact:
for every one human, there are 1 million
arthropods on Earth
Exoskeleton
 Strong
 Protective
 Flexible at the joints
Segmentation & Appendages
 Variety of appendages ►
efficient locomotion
Legs (walking, hopping, swimming)
Wings (flying)
Segmentation & Appendages
 Variety of mouth parts ►
many feeding patterns
Respiration:
Air Piped Directly to Cells
 O2 direct to muscles ► spiracles to tracheae
permits rapid movement
Highly Developed Senses
 Touch E.g. antennae, sensilla
 Smell / chemosensors
 Hearing / Vibration E.g. tympanae (# 11)
 Balance
Complex Behaviors
1. Insect Societies
(division of labor)
2. Many innate behaviors
(genetically programmed)
permit survival
E.g.
* weaving of
spider webs,
* building of bee hives,
* bee dances
Bee dances
 Dance performed in hive
 Pattern indicates distance &
direction of food source
Bee Dance- Round Dance
 This is used when the source of food (nectar
or pollen) is less than 100 meters away
Bee Dances- Waggle Dance
 For food supplies more than 100 meters the
waggle dance is used.
Metamorphosis
Two Types:
1. Incomplete
young look like mini
adults
egg →nymph
(instar)→ adult
E.g. grasshopper,
arachnids, centipedes,
millipedes
Metamorphosis
2. Complete
young do NOT look like
adults
egg → larva
→
pupa (cocoon/chrysalis)
→ adult
E.g. bees, butterflies,
moths, beetles
Why So Successful?
Why So Abundant?
What are six reasons that Arthropods are so
successful?