Lecture Notes on Feline Senses

Introduction

• Cats have sensory abilities inherited from their wild ancestors.
• These abilities allow them to experience the world differently compared to humans.

Sight

Night Vision

• Cats can see better in low light, not in complete darkness.
• Photoreceptors:
  • Rods: More numerous in cats, three times more than in humans, allowing for better low-light vision.
  • Cones: Responsible for color vision, less prominent in cats.
• Eye Structure:
  • Large eyes with elliptical pupils that can greatly dilate for increased light intake.
  • Tapetum lucidum: Reflects light back through the retina, enhancing night vision by 40%.

Movement Detection

• Saccades help track fast movements accurately.
• Cats can perform corrective saccades at twice the speed of humans.
• Slow movement detection is less effective compared to humans.

Visual Focusing

• Cats have inflexible lenses, focusing by lens movement, not distortion.
• Better at focusing on distant rather than close objects.

Color Vision

• Limited color perception with cones sensitive to blue and green.
• Likely see blue and yellow as primary colors.
• Cats are more oriented towards distinguishing shapes and brightness over colors.

Binocular Vision

• Cats have stereoscopic vision for depth perception.
• Some Siamese cats may lack full stereoscopic vision due to genetic issues.

Field of Vision

• Similar binocular field to humans but a wider peripheral field (200° compared to 180° in humans).

Hearing

• Cats have a wide hearing range (48 Hz to 85 kHz) but are best up to 60 kHz.
• Can hear high-pitched sounds like those from rodents.
• Sensitive hearing, though less adept at detecting minor sound differences compared to humans.
• Pinnae (ear flaps) can move independently to locate sound sources.

Olfaction (Sense of Smell)

• Critical for communication, reproduction, feeding, and hunting.
• Olfactory Epithelium:
  • Larger surface area than humans, with 200 million receptors.

Vomeronasal Organ

• Known as Jacobson's organ, present in cats but not humans.
• Detects pheromones and plays a role in social communication.
• Flehmen response is a behavior indicating its use.

Touch

Whiskers (Vibrissae)

• Different types located on the face and legs.
• Sensitive to pressure and air currents, aid in hunting and navigation.

Feet

• High density of mechanoreceptors for detecting vibrations and exploring.

Balance

Vestibular System

• Inner ear structure responsible for balance.
• Semicircular canals and otolith organs detect movement and gravity.
• Cat's vestibular system provides clear and precise balance information.

Righting Reflex

• Allows cats to land on their feet when falling.
• Involves head rotation first, then body, using a flexible spine.
• Requires sufficient fall distance to fully execute.

References

• Various studies and publications provide insights into the anatomy and physiology of cat senses.