Chapter Lecture Outline
How Are We Related to the Neanderthals?
The role of molecular biology in systematics (Chapter 12 and Module 15.12).
Focus on the role of molecular biology in systematics.
Neanderthals lived in Europe until approximately 30,000 to 40,000 years ago. They had a
large brain, could make tools with stone and wood, and were short in stature with heavy
muscles. The Neanderthal skull (left) was markedly different from the Cro-Magnon skull
(which is a direct ancestor of modern Europeans; right).
A question was raised recently regarding the possibility of interbreeding between Cro-
Magnons and Neanderthals. To help answer the question, molecular techniques were used
to sequence the DNA from a piece of Neanderthal bone. The results were compared to
DNA of modern humans, regardless of location on Earth.
Little, if any, genetic contribution from Neanderthal to modern humans was seen in the
DNA from another Neanderthal bone (an infant) was analyzed, and the previous result was
corroborated (no interbreeding occurred).
The DNA comparison was repeated with four more Neanderthal bones, and the results were
the same: no similarities, no recognizable interbreeding between Cro-Magnon and
The central issues of this chapter are tracing our primate heritage, the not-entirely-worked-out
evolutionary pathway of humans, and the pathway of cultural evolution and its effect on the
I. Primate Diversity
The human story begins with our primate heritage.
Geological timeline (Module 15.1) and the comparison of human and baboon skeletons
Primates include lemurs, tarsiers, monkeys, and apes. Humans are part of the ape group. The
earliest primates were small, arboreal creatures that lived at the end of the Age of Dinosaurs, 65
million years ago (mya) (Module 15.1).
Most living primates are arboreal, and humans (never strictly arboreal) retain in their bodies
many traits that evolved with our arboreal relatives. Primitive primate characteristics, as
exhibited by the slender loris (Figure 19.1A), include flexible shoulder and hip joints,
maneuverable hands and feet, opposable thumbs and big toes, sensitivity to touch in the hands
and feet, short snout, and eyes close together at the front (enhancing three-dimensional vision).
The lorises, pottos, and lemurs form one group of primates (Figure 19.1B). All live in tropical
forests, and all are threatened by habitat destruction. Of approximately 50 species of lemur to
live on Madagascar, 18 are extinct because of human incursion into their habitat about 2,000