Lecture 3

Question 1

Backbone (spine)

Answer 1

• Quadrupeds: arch-shaped spine (kyphosis)
• Gorillas, chimpanzees: Spine in the neck area has a curve, which is oriented forward (lordosis)
  
  • These enables vertical position of the head
• Human: lordosis present also in the lumber area (double S shape)
  
  • Enables erect posture

Question 2

Chest

Answer 2

• Quadrupeds, lower primates: lateral flattened chest
• Gorilla, chimpanzee: chest in barrel-shaped
• Human: dorso-ventral flatness of the chest
  
  • Ribs hang downwards because of upright posture

Question 3

Pelvis

Answer 3

• Monkeys: Narrower and deeper pelvis than humans
• Human: Pelvis extended in the shape of a basin, it is also shallower
  
  • Extended pelvis gives beter support to the intestine when upright
  • It transmits the mass of upper body to the lower extremities
  • Different attachments of the muscles:
    
    • In humans they are moved toward the middle of ilium
    • They prevent the body from falling aside
    • Due to bipedalism, humans have smaller supportive surface, then other mammals

Question 4

Extremities

Answer 4

Apes - brachiators
- Longer, better developed upper extremities
- Longer forearms than upper arms
Humans: better developed legs
- Tibia is longer than femur
- Femur is positioned at an angle according to the knee
- In humans, complete extension of the knee junction is possible
- It enables long term upright standing
- Long legs: the body moves less up-and-down while running
- Lower energy consumption
- More sweat glands: more efficient cooling

Question 5

Foot

Answer 5

Primates
- Grasping feet
Humans
- Non-grasping feet - firm standing possible
- Strongly developed heel bone (calcaneus)
- Thumb is the strongest finger
- As it is the point of last contact with the surface during a step
- Longitudialy and diagonally arched foot
- Amortization and elasticity

Question 6

Skull

Answer 6

Differences because of upright posture and intensive development of brains in humans
Prosimi
- Orbits without the back wall
- Orbit = bony wall that surrounds the eye
- Worse stabilisation of the eye
- Lateral position of eyes
- Snout
Apes (Hominidae)
- Closed orbits
- Strong facial region
- Extended skull (big teeth)
- Tooth arch is angular at the origin of growth of canine teeth
- Diastems: gaps between teeth for canine teeth
- Molars have five tops
- Arches above the eyes and bony reef in the occipital region
- Strong occipital muscles
- They keep the head in horizontal position
- Concave shape of the face
- Jaws are sticking out
- Low nose
Humans:
- Brain region is bigger than facial region
- Foramen magnum is on the bottom part of the skull
- Vertical position of the skull on the spine
- There is no need for strong muscle attachements
- Parabolic tooth arch
- Short canine teeth: circular chewing is possible
- Molars have four tops
- Reduction of teeth
- Chin
- Lifted nose

Question 7

Scruff region

Answer 7

Occipital (os occipitale): 4 lines on the outer surface are visible
- Muscle attachments
- Connection of occiputal bone with processes of cervical vertebra (processus spinosus)
- It is the least distinctive in humans

Question 8

Reproduction

Answer 8

Strepsirrhini: seasonal mating
- More offspring’s at the same time
- Cubs are quite developed at birth
- Sensory systems are functional
- They are capable of adult movement in a few weeks
Antropoidea: Monthly cycle
- Usually only one offspring, exceptoinally twins
- At birth, cubs are helpless
- Sensory systems are only partly functional
- Tight connection with mother
Higher developed primates need more time for growing up and growth

Question 9

Ontogeny

Answer 9

Development and changing of organism from the insemination of an egg cell until death