Chapter 9 Flashcards
Bipedalism
walking upright on two feet
Hominin
humans and all of our extinct bipedal ancestors
and relatives since our divergence from the last common ancestor (LCA) with chimpanzees
Last common ancestor (LCA)
last common ancestor (LCA) with chimpanzees
The hypothetical final ancestor or ancestral population) of two or more taxa before their divergence.
Fossils
The remains or impression of an organism from the past
Paleoanthropologists
people who study human evolution
Encephalization
evolution of a big brain
Morphologically
the study of the form or size and shape of things; in this case, skeletal parts
East African Rift System
Ethiopia, Kenya, Tanzania, and Malawi
Site
A place in which evidence of past societies/species/activities may be observed through archaeological or paleontological practice
Use the terms “bipedal,” “hominin” and “last common ancestor” to explain what happened when our ancestors diverged from chimpanzees.
It’s when we started walking upright is when we deviated from chimpanzees
What do we know for sure about human evolution?
Yet there is still so much to understand. Modern debates now look at the relatedness of these species to us and to one another. New scientific techniques provide us with insight into the diets, environments, and lifestyles of these ancient relatives that was not available to researchers even ten years ago.
Phylogeny
The study of the evolutionary relationships between groups of organisms.
What ideas about human evolution were commonly held at one time but we now know are wrong? (use as many terms from the middle column as possible).
Increases in brain size do not necessarily correlate with an increase in intelligence in animals, especially if body size is not taken into consideration. However, the brain is an expensive tissue to build and maintain
Homo
human genus
Ardipithecus
Ardipithecus is an ancient hominin group that lived in Africa between 5.8 and 4.4 million years ago, before the emergence of Australopithecus and Homo
Paranthropus boisei
Paranthropus boisei is a species of australopithecine from the Early Pleistocene of East Africa about 2.5 to 1.15 million years ago. The holotype specimen, OH 5, was discovered by palaeoanthropologist Mary Leakey in 195
People often believe that brain size correlates with higher intelligence, but explain why this might not necessarily be the case.
Increases in brain size do not necessarily correlate with an increase in intelligence in animals, especially if body size is not taken into consideration
What do researchers basically believe about the brain?
Researchers therefore argue that the cost of maintenance must yield some evolutionary benefit
Taxa
Plural of taxon, a taxonomic group such as species, genus, or family
Taxonomies
The science of grouping and classifying organisms
Cladistics
Cladistics groups organisms according to their last common ancestors based on shared derived traits
The field of grouping organisms into those of shared ancestry
For example, if we use feathers as a trait, we can group pigeons and ostriches into the clade “birds.” Organisms that share the same traits.
Phylogenetics
The study of phylogeny (The study of the evolutionary relationships between groups of organisms).
Derived traits
Newly evolved traits that differ from those seen in the ancestor.
Clade
The field of grouping organisms into those of shared ancestry