Entomology and Arachnids 🐜

Overview of Insects

• Global Population:
  • Estimated 10 quintillion bugs on Earth.
  • Equivalent to over 2,000 bugs per person.
• Common Perceptions:
  • Considered pests: ants, flies, bees, spiders, etc.
• Importance of Insects:
  • Serve various purposes in ecosystems.

Studying Insects: Entomology

• Definition:
  • Entomology: study of insects.
  • Derived from Greek: "entom" (insects) and "ology" (study of).
• Characteristics Common to Insects:
  1. Body Structure:
     • Three sections: head, thorax, abdomen.
     • Examples: grasshoppers, moths, butterflies, ants, mosquitoes, bees.
  2. Anatomy:
     • Pair of antennae on head.
     • Six legs attached to thorax.
  3. Reproduction:
     • Born from eggs.
     • Young insects are called nymphs.
     • Nymphs have a chitin exoskeleton (molting process).
  4. Vision:
     • Compound eyes see all around and detect quick movements.
  5. Flight:
     • Some insects can fly (wings attached to thorax).

Social Insects

• Definition: Insects that live in colonies.
• Categories & Examples:
  1. Integration:
     • Example: Bees
     • Beehive population: 10,000 to 60,000 bees.
  2. Division of Labor:
     • Queen Bee:
       • Lays around 2,000 eggs/day.
       • Releases a scent to signal worker bees.
     • Worker Bees:
       • Female bees with tasks: feeding queen, collecting pollen/nectar, making beeswax, cleaning hive, defense.
     • Drone Bees:
       • Male bees that mate with queen.
  3. Overlap of Generations:
     • Young and old insects coexist in colonies.

Benefits of Insects

• Environmental Benefits:
  • Bees deliver good bacteria, pollinate flowers, spread seeds, produce honey and beeswax.
  • Insects as part of the arthropod family (including spiders).

Arachnids

• Differences from Insects:
  • Examples: Spiders, scorpions, mites, ticks.
  • Body sections: cephalothorax and abdomen.
  • Eight legs, simple eyes, no antennae or wings.
• Spiders:
  • Spinneret produces silk for webs and cocoons.
  • Young spiders are called spiderlings.
  • Help control pest populations.
  • Food for birds, reptiles, and small mammals.
  • Spider venom used in medicines; silk used in materials like bulletproof vests and parachutes.
• Harvestmen (Daddy Longlegs):
  • Belong to arachnids, not spiders.
  • Do not produce venom or silk.
  • Eat plants and small insects.
• Historical Context:
  • Spiders have existed for about 2 million years.

Conclusion

• Insects and arachnids play essential roles in ecosystems.
• Potential benefits in becoming an entomologist.