Human Evolution

Understanding the so-called "missing links" within human evolution

Figure 1

"Missing Link" is still a popular phrase when referring to the fossil record within evolutionary biology as having holes and gaps. Yes, it must be acknowledged that there gaps within the fossil record, however, the only reason the Theory of Evolution is still being discussed is because the fossil record continues to be filled by more and more discoveries of fossils, and each subsequent discovery further solidifies the evidence that evolution is a fact.

If at any point a fossil was found out of order, in the wrong layer of sediment, part of the wrong time period - it would disprove the entire theory. However, what we find is instead more and more fossils accumulating to sufficiently bolster the evolutionary argument.

Thus it would be remarkably easy for Creationists to disprove Evolution if they actually could find evidence to support their position.

As there are thousands of fossils, mostly fragmentary, often consisting of single bones or isolated teeth with complete skulls and skeletons rare, this overview is not meant to be complete, but does show some of the most important finds. The fossils are arranged by approximate age as determined by radiometric dating and/or incremental dating and the species name represents current consensus - if there is no clear scientific consensus the other possible classifications are indicated.

Let's take a close look at the human family tree and the "missing links" that have been uncovered in the 150 years since Darwin.

To begin our evolutionary journey back through time we begin with modern-day humans or Homo sapiens.

Characteristics of Homo sapiens (60,000 years ago - present)

• bipedal
• large skull
• highly evolved brain - language & tool skills

Characteristics of our extinct cousin, Homo neanderthalensis (500,000 years ago - 10,000 years ago)

Homo neanderthalensis

• stocky, adapted to cold
• rudimentary language skills
• tool skills
• large brains and skulls

Characteristics of our extinct cousin, Homo heidelbergensis (500,000 - 1 million years ago)

Homo heidelbergensis

• discovered in Europe
• use of tools & language

Homo sapiens, Homo heidelbergensis, and Homo neanderthalensis are descendants of the next step in the Evolutionary tree (see figure 1 above):

Characteristics of Homo erectus "Java Man" - our "father"(500,000 - 2 million years ago)

fossils of the Java Man

• Brain 60-70% size of modern humans
• tool skills
• basic language capabilities
• hairier
• more pronounced brow and jaw

The "Java Man" is a descendant of Homo ergaster:

Characteristics of Homo ergaster - our "grandfather" (1 million - 2 million years ago)

Homo ergaster

• small face & teeth
• Brain 60% of modern humans
• use of tools
• may have known how to make fire

Homo ergaster is a descendant of Homo habilis:

Characteristics of Homo habilis - our "great-grandfather" (1.5 - 2.5 million years ago)

Homo habilis

• Brain 50% size of modern humans
• language & tool use

Homo habilis is a descendant of the Genus Paranthropus, which descends from the Genus Australopithecus:

Characteristics of Australopithecus africanus - "our great-great-great(etc) grandfather"(3.5 million years ago)

Australopithecus africanus

• bipedal
• brain 40% size of modern humans

Australopithecus africanus is a cousin of Australopithecus afarensis:
Characteristics of Australopithecus afarensis "Lucy" (3 million - 4 million years ago)

Autralopithecus afarensis

• bipedal
• 1.2-1.4m tall
• 35% brain size of modern humans
• Could not use tools

The chart below depicts a more detailed breakdown of the evolutionary path from ape to man, with branches showing additional species that died out before the present day.

Due to the frequency of the misunderstanding, I must draw attention to the fact that humans did not evolve from chimpanzees (which is why they are absent on the chart); we are cousins and thus descended from a common ancestor shared millions of years ago.

The evidence of human ancestry has also unlocked the information regarding where we came from, and we are all Africans.

Map displaying movement of human descendants
out of Africa




*THIS PAGE IS INCOMPLETE*
Projected completion: 6/1/13