The Human Evolution
THE
HUMAN EVOLUTION
Stages in Human Evolution
Who is Early Man?
Australian Aborigines,
Red Indians, Sri Lankan Veddas, Japanese Ainu, Kung Bushmen of Africa, Mayans
of Mexico, etc. were some of the dominant inhabitants of the Earth before the
establishment of the modern man. They are culturally different among
themselves, and the geographical boundaries such as oceans have been the main
extraction. These early men lived with nature and, most importantly, they
sustainably utilized the natural resources.
Indigenous people
lived in tribes had family units while some were nomadic. These un-urbanised
self and sustaining societies had very simple lifestyles with primary hunting
methods and simply sheltered houses. They followed spiritual beliefs more
often. Moreover, the development of technology was very low during the time
they were thriving on the Earth, which was at least several thousand years ago
from the present.
Figure 01: Early Man
Furthermore, the
communication between distant places was primary as they frequently used loud
sounds to signal others. Travelling and transportation took more time and
effort to complete. At present, the indigenous people or true early man is
declining in numbers. There are only about 5000 of them living in over 70
countries.
The following are the stages of human
evolution:
1. Dryopithecus
These are deemed to be the ancestors of both
man and apes. They lived in China, Africa, Europe and India. The genus
Dryopithecus refers to the oak wood apes. When Dryopithecus was alive, the
tropical lowlands which it inhabited were densely forested, so the members
could have predominantly been herbivores.
2. Ramapithecus
Their first remains were discovered from the
Shivalik range in Punjab and later in Africa and Saudi Arabia. They lived in
open grasslands. Two pieces of evidence confirm their Hominid status:
- Thickened tooth enamel, robust
jaws and shorter canines.
- Usage of hands for food and
defence and extrapolations of upright posture.
3. Australopithecus
The fossil of this genus was first discovered in 1924 in South
Africa. They lived on the ground, used stones as weapons and walked erect. They
were 4 feet tall and weighed 60-80 pounds.
4. Homo Erectus
The first fossil of Homo Erectus was found in
Java in 1891. These were named as Pithecanthropus Erectus. These were
considered as the missing link between the man and apes. Another discovery made
in China was the Peking man. This specimen had large cranial capacities and is
believed to have lived in communities. Homo erectus used tools comprising
quartz. Tools made of bones and wood were also discovered. There is evidence of
collective huntings. There is also evidence of the use of fire. The Homo
Erectus is believed to dwell in caves.
5. Homo Sapiens Neanderthalensis
The Homo Erectus evolved into Homo Sapiens.
During evolution, two sub-species of Homo Sapiens were identified- Homo sapien
Neanderthal and Homo sapiens sapiens. The cranial capacity of Neanderthal grew
from 1200 to 1600 cc. Some small hand axes had also been discovered. This
species of hominids could hunt big names such as mammoths.
6. Homo Sapiens Sapiens
The remains of Homo Sapiens were first
discovered in Europe and were named Cro-Magnon. In these, the jaws are quite
reduced, the modern man’s chin appeared, and the skull was rounded. Their
cranial capacity was about 1350 cc. They gathered food through hunting. Art
first appeared during this time.
This is how evolution took place.
All people living today belong to the
species Homo sapiens. We evolved only relatively recently but with complex culture
and technology have been able to spread throughout the world and
occupy a range of different environments.
Homo sapiens background
Homo sapiens age
300,000
years ago to present:
- archaic Homo
sapiens from 300,000 years ago
- modern Homo
sapiens from about 160,000 years ago
What the
name Homo sapiens means
The
name we selected for ourselves means ‘wise human’. Homo is the
Latin word for ‘human’ or ‘man’ and sapiens is derived from a
Latin word that means ‘wise’ or ‘astute’.
Other Homo
sapiens names
Various
names have been used for our species including:
- ‘Cro-Magnon Man’
is commonly used for the modern humans that inhabited Europe from about
40,000 to 10,000 years ago.
- The term
‘archaic’ Homo sapiens has sometimes been used for
African fossils dated between 300,000 and 150,000 years of age that are
difficult to classify due to a mixture of modern and archaic features.
Some scientists prefer to place these fossils in a separate species, Homo
helmei.
- Homo sapiens
sapiens is
the name given to our species if we are considered a sub-species of a
larger group. This name is used by those that describe the specimen from
Herto, Ethiopia as Homo sapiens idàltu or by those who
believed that modern humans and the Neanderthals were
members of the same species. (The Neanderthals were called Homo
sapiens neanderthalensis in this scheme).
The transition to modern humans
The first modern humans in
Southeast Asi
African
fossils provide the best evidence for the evolutionary transition from Homo
heidelbergensis to archaic Homo sapiens and then to
early modern Homo sapiens. There is, however, some difficulty in
placing many of the transitional specimens into a particular species because
they have a mixture of intermediate features which are especially apparent in
the sizes and shapes of the forehead, brow ridge and face. Some suggest the
name Homo helmei for these intermediate specimens that
represent populations on the brink of becoming modern. Late surviving
populations of archaic Homo sapiens and Homo
heidelbergensis lived alongside early modern Homo sapiens before
disappearing from the fossil record by about 100,000 years ago. Key specimens
that reveal an evolutionary transition from archaic to modern Homo
sapiens include Florisbad cranium, LH18 from Laetoli, Omo 1 and 2 from
Omo-Kibish, Herto skull from Ethiopia and Skhul 5 from Israel.
Important
specimens: Late early modern Homo sapiens
- Liujiang – a
skull discovered in 1958 in Guanxi province, South China. Age is
uncertain, but at least 15,000 years old. This skull lacks the typically
northern Asian features found in modern populations from those regions,
lending support to popular theories that such features only arose in the
last 8000 years.
- Aurignac – skull
discovered in Aurignac, France. The first Aurignac fossils were
accidentally found in 1852. A workman digging a trench in a hillside found
a cave that had been blocked by rock but after clearing away the debris he
found 17 skeletons. The skeletons were taken to a local cemetery for
burial but later investigations indicated that the skeletons were actually
up to 10,000 years old.
- Cro-Magnon 1 – a
32,000-year-old skull discovered in 1868 in Cro-Magnon rockshelter, Les
Eyzies, France. This adult male represents the oldest known skull of a
modern human from western Europe. Cro-Magnon skeletons have proportions
similar to those of modern Africans rather than modern Europeans. This
suggests that the Cro-Magnons had migrated from a warmer climate and had a
relatively recent African ancestry.
Important
specimens: Early modern Homo sapiens
- Herto – a
160,000-year-old partial skull discovered in1997 in Herto, Ethiopia. This
skull from an adult male and those of another adult and a child were found
in 1997 and publicly announced in 2003. They are some of the oldest
fossils of modern Homo sapiens yet discovered. Some
scientists regard these fossils as a sub-species of modern humans
(named Homo sapiens idàltu) because of some slight differences
in their skull features. They show a suite of modern human traits, mixed
with archaic and early modern features. Also of significance are cut marks
on the child's skull. These were made when the bone was still fresh in a
manner indicating ritual practice. The skull also appeared 'polished' from
repeated handling before it was laid in the ground.
- Omo 1 – a
partial skull discovered in1967 in Omo-Kibish, Ethiopia. A recently
published date for this skull was about 195,000 years old, but this is
disputed. However, it is still one of the oldest known fossils of early
modern Homo sapiens. Features which show the transition from
an archaic to an early modern Homo sapiens include a more
rounded and expanded braincase and a high forehead. Now dated to the same
age as Omo 2, it does raise interesting questions about why it appears to
have slightly more advanced features than Omo 2. Were they from the same
population?
- Skhul 5 – a
90,000-year-old skull discovered in1932 in Skhul Cave, Mount Carmel,
Israel. This skull of an adult male has developed relatively modern
features including a higher forehead although it still retains some
archaic features including a brow ridge and slightly projecting face. This
specimen and others from the Middle East are the oldest known traces of
modern humans outside of Africa. They prove that Homo sapiens had
started to spread out of Africa by 100,000 years ago, although it may be
that these remains represent a population that did not expand beyond this
region – with migrations to the rest of the world occurring later, about
60-70,000 years ago.
Important
specimens: Archaic Homo sapiens
- LH 18 – skull
discovered in 1976 in Ngaloba, Laetoli, Tanzania. Age is about 120,000
years old (but debated). This skull is transitional between Homo
heidelbergensis and early modern Homo sapiens. It has
a number of primitive features but also has some modern characteristics
such as a reduced brow ridge and smaller facial features. The late date of
this specimen indicates that archaic humans lived alongside modern
populations for some time.
- Florisbad – a
260,000-year-old partial cranium discovered in 1932 in Florisbad, South
Africa. This skull shows features intermediate between Homo
heidelbergensis and early modern Homo sapiens. The
face is broad and massive but still relatively flat and the forehead is
approaching the modern form.
- Omo 2 – a
195,000-year-old braincase discovered in 1967 in Omo-Kibish, Ethiopia.
Like LH 18, this braincase shows a blend of primitive and modern features
that places it as a member of a population transitional between Homo
heidelbergensis and early modern Homo sapiens. Its
primitive features include a heavier, more robust construction; an angled
rather than rounded rear section; and a lower, sloping forehead. Refer to
Omo 1 specimen for interesting comparisons.
Homo sapiens key
physical features
Homo
sapiens skulls have a
distinctive shape that differentiates them from earlier human species. Their
body shape tends to vary, however, due to adaptation to a wide range of
environments.
Homo sapiens Body
size and shape
- the
earliest Homo sapiens had bodies with short, slender
trunks and long limbs. These body proportions are an adaptation for
surviving in tropical regions due to the greater proportion of skin
surface available for cooling the body. More stocky builds gradually
evolved when populations spread to cooler regions, as an adaptation that
helped the body retain heat.
- Modern humans
now have an average height of about 160 centimetres in females and 175
centimetres in males.
- Homo sapiens living
today have an average brain size of about 1350 cubic centimetres which
makes-up 2.2% of our body weight. Early Homo sapiens, however,
had slightly larger brains at nearly 1500 cubic centimetres.
- modern Homo
sapiens skulls have a short base and a high braincase. Unlike
other species of Homo, the skull is broadest at the top. The
fuller braincase also results in almost no post-orbital constriction or
narrowing behind the eye sockets
- back of the
skull is rounded and indicates a reduction in neck muscles
- face is
reasonably small with a projecting nose bone
- brow ridge is
limited and the forehead is tall
- orbits (eye
sockets) are square rather than round
- jaws are short
which result in an almost vertical face
- usually no gap
(retromolar space) between the last molar teeth and the jaw bone
- jaws are lightly
built and have a protruding bony chin for added strength. Homo
sapiens is the only species to have a protruding chin.
- shortened jaw
has affected the arrangement of the teeth within the jaw. They are now
arranged in a parabolic shape in which the side rows of teeth splay
outwards rather than remain parallel as in our earliest long jawed
ancestors.
- teeth are
relatively small compared with earlier species. This is especially
noticeable in the front incisor and canine teeth.
- front premolar
teeth in the lower jaw have two equal-sized cusps (bumps on the chewing
surface)
- limb bones are
thinner and less robust than earlier human species and indicate a
reduction in muscle size from earlier humans.
- legs are
relatively long compared with the arms.
- finger and toe
bones are straight and without the curvature typical of our earliest
australopithecine ancestors.
- pelvis is
narrower from side-to-side and has a deeper bowl-shape from front-to-back
than previous human species.
Homo sapiens
Lifestyle
How do we know how they
behaved?
Homo sapiens Culture
and technology
The
earliest Homo sapiens had a relatively simple culture,
although it was more advanced than any previous species. Rare evidence for
symbolic behaviour appears at a number of African sites about 100,000 years
ago, but these artistic expressions appear more of a flicker of creativity than
a sustained expression. It is not until about 40,000 years ago that complex and
highly innovative cultures appear and include behaviour that we would recognise
as typical of modern humans today.
Many
researchers believe this explosion of artistic material in the archaeological
record about 40,000 years ago is due to a change in human cognition - perhaps
humans developed a greater ability to think and communicate symbolically or
memorise better. However, as there are obvious attempts at art before this,
perhaps there are other reasons. One theory is that population size and
structure play a key role as social learning is considered more beneficial to
developing complex culture than individual innovations are. Bigger populations
often accumulate more cultural attributes than isolated groups.
Homo sapiens Tools
Initially, Homo
sapiens made stone tools such as flakes, scrapers and points that were
similar in design to those made by the Neanderthals (Homo neanderthalensis).
This technology appeared about 250,000 years ago, coinciding with the probable
first appearance of early Homo sapiens. It required an ability for
abstract thought to mentally plan a series of steps that could then be
executed. Only a small number of tools were produced from each core (the
original stone selected for shaping) but the tools produced by this
prepared-core method maximised the cutting edge available. Historically,
archaeologists used different terminologies for Lower Palaeolithic cultures in
different parts of the world. Many of these terms are now consolidated within
the Mode 3 technology to emphasise the similarities between these technologies.
As
more sophisticated techniques developed in some parts of the world, this early
Mode 3 technology was replaced by either Mode 4 or Mode 5 technology and the
use of a wider range of materials including bone, ivory and antler. Mode 4
technology first appeared in Africa about 100,000 years ago. It is
characterised by the production of long, thin stone flakes that were shaped
into long blade knives, spearheads and other tools. Mode 5 technology
specialised in the production of very small blades (microliths) that were often
used in composite tools having several parts. These tools included small-headed
arrows, barbed spears and sickles. Regional variation in these tool cultures
developed with an influx of new styles and techniques especially within the
last 40,000 years, including the Magdalenian and Aurignacian.
Homo sapiens use
of Fire
Sophisticated
control of fire, including complex hearths, pits and kilns, allowed Homo
sapiens to survive in regions that even the cold-adapted Neanderthals
had been unable to inhabit.
The
Cro-Magnon site at Dolni Vestonice in the Czech Republic produced the earliest
evidence for high temperature kilns and ceramic technology. The kilns, dated at
26,000 years old, were capable of firing clay figurines at temperatures over
400 degrees Celsius. About 2000 fired lumps of clay were found scattered around
the kiln.
Homo sapiens Clothing
and personal adornment
Animal
hide clothing may have been worn in cooler areas, although direct evidence of
clothing only exists for the last 30,000 years. This evidence includes
specialised tools such as needles; adornments such as buttons and beads sewn
onto clothing; and the remains of animals, such as arctic foxes and wolves,
that indicate they were trapped for their fur. Clothes that were sewn provided
better protection from the cold than clothes that were merely tied together.
Fibres
from flax plants were discovered in a cave in Georgia in 2009, dating to about
36,000 years old. The flax was most likely used to make clothes and woven
baskets, and a small number appear to be dyed. They are the oldest example of
their kind ever found. Textile impressions have been discovered at other
European sites have, but no actual remains.
Items
of personal adornment not sewn onto clothing include ivory, shell, amber, bone
and tooth beads and pendants. Ostrich eggshell beads that date from about
45,000 years ago have been found in Africa, as well as pierced shell beads in
Morocco dating to 80,000 years ago and marine shell beads from Israel dating to
90,000 years old, but body adornment only become prolific from about 35,000
years ago.
One
of the earliest known pendants is a horse carved in mammoth ivory from
Vogelherd, Germany. It is dated at 32,000 years old. Body adornments like this
are evidence that humans had progressed from merely trying to survive and were
now concerned with their appearance.
Homo sapiens Art
Cave
art began to be produced about 40,000 years ago in Europe and Australia. Most
of the art depicts animals or probable spiritual beings, but smaller marks in
many caves in France, and possibly others in Europe, are now being analysed as
they may be a written 'code' familiar to many prehistoric tribes. In
particular, 26 symbols appear over and over again across thousand of years,
some of them in pairs and groups in what could be a rudimentary 'language'.
These suggest that early Europeans were attempting to represent ideas
symbolically rather than realistically and share information acorss
generations. The oldest of these symbols date to about 30,000 years old.
Evidence
of musical instruments first appeared about 32,000 years ago in Europe.
Palaeolithic bone flutes and whistles from various sites in France range in age
from 30,000 to 10,000 years old.
Portable
artwork, such as carved statuettes, first appeared about 35-40,000 years ago in
Europe. Venus figurines were widespread in Europe by 28,000 years ago.
Fragments from Germany found in 2009, suggest their origins started at least
35,000 years ago. An ivory female head with bun from Dolni Vestonice, Czech Republic,
is one of only 2 human head carvings from this period that show eye sockets,
eyelids and eyeballs. It is dated at 26,000 years old.
Red
ochre pieces from Blombos Cave in South Africa, dating to about 100-80,000
years ago, show evidence of engraving that may be an expression of art or
simply incidental marking made during other activities. However, other signs of
possible symbolic behaviour, including shell beads and sophisticated tools
(known as Still Bay points) have also come from this site, strengthening the
case for early artistic expression.
Homo sapiens Settlement
Early Homo
sapiens often inhabited caves or rock shelters if these were
available. More recently, especially within the last 20,000 years, natural
shelters were enhanced with walls or other simple modifications. In open areas,
shelters were constructed using a range of framework materials including wooden
poles and the bones of large animals, such as mammoths. These structures were
probably covered with animal hides and the living areas included fire hearths.
Living
sites were much larger than those occupied by earlier humans and a comparison
with modern traditional peoples suggests that clans consisted of between 25 and
100 members.
How early human ancestors died
Burial
Burials
were infrequent and very simple prior to 40,000 years ago and then began to
become more elaborate with the inclusion of valued objects such as tools and
body adornments. Red ochre was sprinkled over many of the bodies prior to
burial.
One
of the earliest deliberate burials of a modern human comes from Jebel Qafzeh in
Israel. Dating to 90,000 years old, the grave contains the bones of a young
woman buried with a young child at her feet. An additional 21 skeletons were
found in the same cave.
Environment and
diet
Early
modern humans were adapted to life in the tropics but by 40,000 years ago they
occupied a range of environments across the continents of Africa, Europe, Asia
and Australia. Within the last 20,000 years humans have also spread into the
Americas. Today, our culture and technology allows us to live in most
environments on our planet as well as some off our planet.
All Homo
sapiens were once hunter-gatherers living on wild plants and animals.
It was only about 11,000 years ago that humans began to domesticate plants and
animals although wild foods still remained important in the diet. Our species
has a wide-ranging and essentially omnivorous diet. This has enabled us to
utilise the food resources found in the wide variety of environments we
inhabit.
Who is Modern Man?
Modern man shares vast
different cultures among continents as well as among countries. In addition,
these cultural differences could extend even more within a country. With the
globalization taking place, those cultural differences will become narrower.
Physical barriers within modern men could not restrict them to isolate from
others as the technologies improved the travel and transport over oceans and
even through aerial routes.
Figure 02: Modern Man Hritik Roshan
Hence, the lifestyle
of modern man is complex with increasing needs for several things such as food,
shelter, power, money, attraction, etc. Hunting has become a least interested foraging
method. Therefore, livestock management has become prominent for the need of
proteins. One of the sounding characteristics of the modern man is the
development of communication techniques. Through the internet, e-mailing,
social networking, and telephones communication has developed. However, the
modern man is still in the increasing mode in terms of population size; it was
almost 6. 8 Billion by 2009.
Thank You for reading
Best wishes from
Suvendu Singha (India, Odisha, Balasore,
Jaleswar)
Nice blogs
ReplyDeleteCarry on 👍
ReplyDeleteVery good writing sir love from America
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