Flashcards in Lecture 12.1 Deck (25):
Why do the gluteal muscles in apes have an extensor role rather than an abductor role in apes?
Head and neck of the femur are smaller in apes than humans meaning bicondylar angle is also smaller and as a result the gluteal muscles perform a different action on the femur.
What is the difference in femoral condyle shape between humans and apes?
Femoral condyles in humans are longer and more elliptical. This allows greater articular contact between femur and tibia making this joint more stable.
Why do apes have a rounded femoral condyle?
Rounded condyle allows apes to have a more unstable but mobile knee.
What is the difference between the tibia and fibula in apes and humans?
Humans have a robust tibia and not as robust fibula. In apes tibia is not as robust but fibula is more robust and mobile.
What is the difference in femoral condyle size between humans and apes?
lateral tibial condyle is smaller than the medial condyle in both humans and apes. In apes the difference is bigger than in humans this allows them to do more rotation
What is different about foot structure between humans and apes?
Human foot has strong heel and well developed arches. Apes have no arch and feet are used to grab onto branches.
What is the function of psoas minor in apes?
Psoas minor inserts oonto pelvis and this helps in maintaining hip flexion (apes always have a flexed hip and flexed knee in their gait)
What is the difference between gluteus maximus between humans and apes?
Gluteus maximus has a wider area of insertion compared to humans.
What is the origin and insertion of the gluteus maximus in apes?
Gluteus maximus originates at ilium, sacrotuberous and sacrospinous ligaments, and at the sacrum and inserts onto the shaft of the femur.
Do apes have a quadratus plantae?
Yes, but in apes the quadratus plantae is frequently absent
What is the function of gluteal muscles in apes?
Gluteals are extensors of the thigh in apes.
What does fossil evidence indicate about the habitat of homo neanderthalensis?
Homo neanderthalensis were adapted to cold weather
What is facial prognathism?
facial prognathism is the projection of the snout
How were the size and shape of the rib cage and pelvis different in australopithecus afarensis compared to apes?
australopithecus afarensus had a cone shaped rib cage combined with a pelvis that's shorter.
When did homo species evolve?
2 million years ago the more modern human features began to appear. (first homo species began to exist)
How are the cervical vertebrae different in australopithecus afaresnsis different to modern humans?
Australopithecus afarensis have long- non bifid spinous processes.
What curvature could be seen in Australopithecus' spines?
australopithecus afarensis had thoracic kyphosis.
In what way is the spine in A. africanus similar to apes?
A. africanus had 6 lumbar vertebrae
Did humans or neanderthals have a larger lumbar lordosis?
Lumbar lordosis in neanderthals was larger than in humans
How was the intermembral ratio different in homo and australopithecus species different?
intermembral ratio in early homo species is very similar to homosapiens and A. species are closer to apes
What structure do australopiths share with knuckle walkers?
Early australopiths have remnant (perhaps vestigial) ridges on their posterior radius
Were neanderthals able to perform precision and power grips?
Saddle joint in neanderthals is not as efficient as modern humans. Precision grip was not possible but power grip was.
Why can it be hypthesized that A. afarensis gave assisted births?
A. afarensis has a narrow pelvic inlet.
What features did the neanderthal pelvis compared to humans?
A more anterior sacrum
A wider pelvis
A long pubis