At this website by various means we seek to defend life, to encourage Christian faith, to promote Catholic tradition, to edify Marriage in its link to the Creator, to encourage families and individuals, and to support missionary disciples of Jesus. G.S.
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Field work in Archaeology and Paleoanthropology is constantly turning up new evidence, which requires adjusting our theories about human origins, the appearance and extinction of species, and the migration of populations. Here are a number of fascinating links to explore.
https://www.nhm.ac.uk/discover/homo-erectus-our-ancient-ancestor.html
https://www.nhm.ac.uk/discover/human-evolution.html
https://www.historymuseum.ca/neanderthal/
https://www.sciencemag.org/news/1996/12/early-human-species-may-have-coexisted-our-own
NATURAL HISTORY
MUSEUM
Human origins
http://www.nhm.ac.uk/nature-online/life/human-origins/early-human-family/index.html
1,800,000 – 200,000 BC Homo
erectus
http://www.nhm.ac.uk/nature-online/life/human-origins/early-human-family/homo-erectus/index.html
900,000 - 700,000 BC Homo
antecessor
http://www.nhm.ac.uk/nature-online/life/human-origins/early-human-family/homo-antecessor/index.html
600,000 - 250,000 BC Homo
heidelbergensis
400,000 – 125,000 BC Homo
rhodesiensis
http://humanorigins.si.edu/evidence/human-fossils/fossils/kabwe-1
http://www.bradshawfoundation.com/origins/homo_rhodesiensis.php
400,000 - 35,000 BC Homo
sapiens neanderthalensis
http://www.nhm.ac.uk/nature-online/life/human-origins/early-human-family/neanderthals/
http://archaeologyinfo.com/homo-neanderthalensis/
400,000 – present BC Homo
sapiens sapiens
http://www.nhm.ac.uk/nature-online/species-of-the-day/evolution/homo-sapiens/
95,000 – 17,000 BC Homo
florensiensis (The Hobbit)
60,000 – 40,000 BC Denisovans
http://www.nhm.ac.uk/nature-online/life/human-origins/early-human-family/denisovans/index.html
Homo erectus Reconstruction
of early Homo erectus
Homo erectus was the first of our relatives to have human-like
body proportions, with shorter arms and longer legs relative to its
torso.
H. erectus was also the first hominin known to have migrated
out of Africa, and possibly the first to control fire and cook food.
Highly varied and by far the longest-lived of all the human species, H.
erectus survived from about 1.8 million years ago in Africa and
western Asia to possibly as late as 200,000 years ago in Indonesia.
Key
fossils Replica fossil skull of
'Turkana Boy', a male Homo erectus aged 9-12 years old.
Although evidence suggests that H. erectus originated in Africa,
the first fossils were found in Asia, and it is in Asia where this species
survived for so long.
The first H. erectus fossil was found in Java, Indonesia in 1891,
and is commonly known as Java Man. By 1940 many more remains had been
found there, and in China.
However, the find that has revealed most about this species is ‘Turkana
Boy’ from Nariokotome, Kenya. Unearthed in 1984, the skeleton is around
1.5 million years old and represents the most complete ancient human
specimen ever discovered.
By studying his remains, scientists have concluded that H. erectus did
not use trees for safety or as a food source like earlier hominins.
Instead, they were a tall species that walked and ran in much the same way as
we do.
Successful species?
In terms of species survival, H. erectus is a huge success story.
Fossil evidence for H. erectus stretches over more than 1.5 million
years, making it the longest surviving species of all our human relatives.
Compare this to our own species, Homo sapiens, which has been around for
perhaps 400,000 years so far, and we begin to appreciate the ability of this
species to survive over a long period with many changes to the environment
and climate.
Beyond Africa
Current evidence suggests all hominins before H. erectus lived in
Africa. However, almost as soon as this species appears in the fossil record
there is evidence it expanded out of Africa into western and eastern Asia
and Indonesia.
Migration happens for many reasons but essentially H. erectus
probably drifted across northern Africa, across the Sinai region into Asia,
when suitable habitats and food sources stretched that far. Meat was an
important part of their diet and carnivorous animals often range more widely
than herbivores. This, together with their larger body size, helps explain the
large geographic range of H. erectus.
Homo heidelbergensis Homo heidelbergensis reconstruction
Homo
heidelbergensis is known
to have lived from at least 600,000 years ago in Africa and Europe to
maybe as late as 250,000 years ago in some areas.
They
routinely butchered large animals, and their fossil remains are often
associated with handaxes.
Evidence suggests that African H. heidelbergensis could be the
ancestor of our own species, Homo sapiens.
Distinctly human
Replica of the Broken Hill skull from Kabwe, Zambia, the finest known example of Homo heidelbergensis
After 1
million years ago, we see different human species living across Asia and Europe
as well as Africa, which are thought of as distinctly human in physique and
behaviour. The first fossil identified as H. heidelbergensis was a jaw
discovered near Heidelberg, Germany in 1907. Since then various
other finds have been made in Europe, Asia and Africa. They show a less
projecting face, more prominent nose and a bigger braincase than Homo
erectus, but also more primitive features than those of Neanderthals and
modern humans.
Some H.
heidelbergensis individuals had brain sizes within the modern human
range. However, facially they still looked very different from us, with a longer,
lower shaped skull, large brow ridge and no chin.
Skilled and organised
Evidence
shows that H. heidelbergensis was an accomplished tool-maker and skillfully
butchered large animals. The remains of horses, elephants, deer and
rhinoceroses with butchery marks on their bones have been found alongside
fossils of this hominin in Southern England and Germany. Whether they actively
hunted the animals isn’t known. But, even if they scavenged the carcasses,
these hominins were organised enough to drive off dangerous competing animals
such as lions, hyenas and wolves.
Common ancestor
Neanderthal
and Homo sapiens DNA reveals that they shared a common ancestor about 400,000
years ago. Many scientists think this could have been H. heidelbergensis,
giving rise to Neanderthals in Europe and to our species in Africa.
And perhaps to the Denisovans in Asia.
Homo rhodesiensis
Nickname: Rhodesian
Man
Site: Kabwe,
Zambia Date of
discovery: 1921 Discovered by: Tom Zwiglaar
Age: Between 300,000 and 125,000 years old Species: Homo
heidelbergensis
Searching for metal ore deposits in the limestone caves of Kabwe, Zambia,
Swiss miner Tom Zwiglaar is credited with finding the first early human fossil ever to be discovered in Africa. When Kabwe
(also known as Broken Hill) was sent to Arthur Smith Woodward, Woodward
assigned the specimen to a new species: Homo
rhodesiensis. Today, most scientists assign Kabwe to Homo
heidelbergensis.
Kabwe shows features similar to H. erectus such as a low braincase
profile (the area towards the back of the skull), large brow ridges, a
slight widening of the midface known as the sagittal
keel, and a protrusion at the back of the skull named the occipital torus.
But Kabwe also resembles modern humans with a flatter, less prognathic face, and larger brain (1300 cubic
centimeters).
This skull is one of the oldest known to have tooth cavities. They occur in
10 of the upper teeth. The individual may have died from an infection
related to dental disease or from a chronic ear infection.
 Image Credit: Jim Di Loreto and Don Hurlbert, Smithsonian Institution |
Bradshaw Foundation
Homo
rhodesiensis is an extinct hominin species living between 400,000 and 125,000
years ago. It is known as 'Rhodesian man'. The fossil Kabwe skull is the type
specimen of this species, found at Broken Hill in Northern Rhodesia, now
Zambia, by Tom Zwiglaar in 1921.
Homo
rhodesiensis was robust, with very large brow ridges and broad face. It is also
referred to as 'African Neanderthal', although it demonstrates intermediate
features between Homo sapiens and Homo neanderthalensis, with a close association to Homo heidelbergensis. It has been argued that it was the ancestor of Homo sapiens idaltu - 'Herto Man' - which itself was the ancestor of Homo sapiens sapiens.
Neanderthals
(Homo neanderthalensis)
http://www.nature.com/news/modern-human-genomes-reveal-our-inner-neanderthal-1.14615
Neanderthals began to evolve about 400,000 years ago, and
survived in Europe and Asia until around 35,000 years ago. Meanwhile
modern humans (Homo sapiens) were evolving in Africa. Thanks to an
abundance of fossil evidence, we have a good idea of what Neanderthals probably
looked like. The animation above shows a typical Neanderthal man. His large
nose and strong
double-arched brow ridge distinguish him from a modern human.
Who
were the Neanderthals?
Illustration of a Neanderthal woman. © John
Sibbick / Natural History Museum
Hundreds of Neanderthal fossils have been found since the first
identified in 1856 in the Neander Valley, Germany, allowing us to
build up an almost complete picture of a typical Neanderthal body.
They had large brains and short, stocky physiques suited to living in
cold environments. Their big nose was also adapted to warming and
humidifying the air.
Neanderthals were skilled hunter-gatherers, made and used flint and
stone tools, built shelters and controlled fire. They were highly
carnivorous but they also ate other foods, although only limited evidence
of plant foods survives in the archaeological record. In Mediterranean regions
the Neanderthals exploited marine resources such as shellfish and seals,
but their use of aquatic foods was certainly more limited than that of modern
humans.
Neanderthals behaved strikingly like our own species in some ways. As well
as making and wearing clothes and probably also simple jewellery,
archaeological evidence also suggests that they buried their dead.
A close relative
Neanderthal burial site at Kebara, Israel. Some scientists believe that such sites suggest that Neanderthals honoured their dead.
Fossil and genetic data suggest that Neanderthals shared a common
ancestor with our species around 400,000 years ago, thought by many
scientists to be Homo heidelbergensis.
In 2010, most of the Neanderthal genome was mapped and compared to modern
populations of Homo sapiens, revealing that the Neanderthals'
relationship to some modern humans was even closer than previously thought. The
results showed that people in Europe, Asia and New Guinea have around 2.5%
Neanderthal DNA in their genetic code, suggesting Neanderthals interbred
with modern humans not long after they spread out of Africa.
Why did the Neanderthals die out?
All physical evidence of the Neanderthals disappears around 30,000 years
ago. Modern humans reached Europe around 15,000 years earlier and it has
been suggested that superior brains, language and skills allowed them to
prevail over the Neanderthals. However, this may underestimate our relative.
An alternative view suggests that Ice Age climate fluctuations
affected European flora and fauna, causing the disappearance of familiar plants
and animals, and that modern humans were better able to adapt than
Neanderthals.
Carolus Linnaeus © Wikimedia
Taxonomy Homo sapiens
Empire Eukaryota
Kingdom Animalia
Phylum
Chordata
Class Mammalia
Order Primates
Family Hominidae
Genus Homo
Species
sapiens
Homo
sapiens is the
most widely dispersed and numerous medium-large size mammal, and the only
extant member of the genus Homo.
The type
specimen of Homo sapiens is Carl Linnaeus (1707–1778), based on the
descriptions in the 10th edition of his Systema Naturae (Linnaeus, 1758).
No single
person was recognised as the type specimen until 1959, when William Stearn
wrote that "Linnaeus himself, must stand as the type of his Homo
sapiens". This was enough to designate Linnaeus as a lectotype - the
single name-bearing type specimen for the species Homo sapiens.
Genus
characteristics include a high degree of encephalisation and a skeleton adapted
to habitual bipedalism. Species traits include:
- a globular cranial vault
- supraorbital ridges small or
absent
- a chin on the lower jaw
The origins of humankind on Earth
It is
estimated that the first members of the human family (hominins) lived in Africa
about 6 or 7 million years ago. They are believed to have been
forest-dwelling, perhaps walking upright in the trees or when on the
ground.
In 2001,
cranial fossils of Sahelanthropus tchadensis dating to this time
were uncovered in Chad, central Africa. The fossils show a combination of ape-like
and human-like features, although how closely related Sahelanthropus
tchadensis is to humans is the subject of debate.
Over
millions of years, distinct species and lineages emerged and radiated across
Africa. Among them were the earliest members of the genus Homo,
to which modern humans belong.
The earliest
fossil evidence of these ancient humans dates to between 1.9 and 2.4
million years ago, and comes from East Africa, although a human-like form
of the species Australopithecus has recently been described from South
Africa. Australopithecus sediba is 1.98 million years old and is
the most human-like australopithecine yet discovered, with an increased front
brain cavity and small teeth.
The emergence of modern humans
Fossil
evidence suggests that modern humans evolved in East Africa around 200,000
years ago, since fossils more than 150,000 years old are known
from Ethiopia and Kenya. However, genetic data from recent African populations
suggests that other regions may also have been important.
One study
compared the DNA of modern hunter-gatherers. The results revealed that
Namibian and Khomani Bushmen of southern Africa, Biaka Pygmies of Central
Africa and the Sandawe of East Africa have the highest levels of genetic
diversity in the world for the DNA studied.
Although
genetic studies should be treated with caution when it comes to pinpointing
origins, genetic diversity is one indicator of how ancient a people are.
In principle the more ancient the population, the more time it has had to build
up diversity.
Human
diversity
Humans
occupy most terrestrial environments and are the most abundant medium-sized
mammal on earth. Putative early members of the species lineage are known from
Africa at more than 250,000 years ago, while examples showing the modern
anatomical pattern date from 195,000–100,000 years ago in Africa, and
90,000–120,000 years ago in the Middle East.
The
earliest well-dated diagnostic Homo sapiens fossils in Europe, eastern
Asia and Australasia date from 40,000–45,000 years, and in the Americas from
less than 15,000 years.
Vitruvian
man by Leonardo da Vinci
Morphology
Humans
can be distinguished from other living apes by a strikingly enlarged brain,
reduced hair coverage on most parts of the body, and by a suite of skeletal and
muscular adaptations associated with habitual bipedal locomotion, including the
loss of the grasping ability of the foot. Humans are terrestrial bipeds with a
limited ability to swim and dive that must be learned.
The
species shows strong variation in body size and proportions, and pigmentation,
some of which can be related to the wide range of environments in which Homo
sapiens lives. Humans exhibit moderate sexual dimorphism in body size.
Nutrition
Humans
are opportunistic omnivores, showing remarkable ingenuity in extracting,
producing, processing and preserving foods. Humans are the only species that
can control or make fire, and cooking is practiced by all known extant human
groups.
Regional
variations in diet are influenced by availability within a particular
environment, by cultural traditions such as food preferences and avoidances,
and even genetic factors. Lactase persistence, which allows some people to
consume milk and dairy products throughout life, is a recent adaptation to
dairy consumption that would only have been useful among populations with a
tradition of dairy farming.
Life cycle
Human
social structure is highly variable. Traditional arrangements that may be
formalised through marriage include monogamous pairs as well as one-male multi
female groups and, more rarely, one-female multi-male groups.
Both
males and females may disperse from their natal community. Human infants are
born in a relatively immature state and remain dependent on adult carers for
several years.
Inter
birth intervals are relatively short such that females may have multiple
dependent offspring at different stages of developmental maturity. Other
members of a community or extended family network may contribute to the care of
dependent children, including fathers, older siblings and grandparents.
Behaviour
A shell
bead from Skhul Cave in Israel, dated to 100,000 years ago.
The
beginnings of modern human cultural complexity can be traced back at least
100,000 years in Africa and the Middle East. African sites have extensive
evidence of the use of red iron oxide pigments, for colouring shell beads and
(probably also) the human body, while in the Middle East there are cave sites
in Israel with shell beads (one is pictured from the site of Skhul), pigments,
and human burials with associated grave goods such as deer antlers.
Behaviour
includes complex treatment of the dead, and symbolism including:
- representational art
- music
- religious beliefs
- complex language
- complex social systems
Conservation
·
An arial
view of London showing a range of human activities. © S Humphrey
·
Human
activities, associated with a rapidly increasing demand for food, timber,
fibre, and fuel have profoundly affected the ecosystems on which humans and
other species depend for their well-being.
·
In the
past century the scale and complexity of human activity has increased to the
point where human activities are threatening other species and also affecting
our own wellbeing as a result of environmental degradation and the likelihood
of humanly-induced global warming.
Homo floresiensis (the 'hobbit')
Model of the skull of Homo floresiensis, the
small, human-like species nicknamed ‘the hobbit’.
In 2003, archaeologists on the island of Flores, Indonesia, made what
has proved to be an extraordinary find. They unearthed the skeleton of a 1m-tall
individual, nicknamed ‘the hobbit’, with some human-like features
yet a small, chimpanzee-sized brain. Analysis revealed it to be just 18,000
years old. This new human species was named Homo
floresiensis and since its discovery other fossils have been found that
suggest this strange hominin lived between 95,000 to as late as 17,000
years ago.
Why was the hobbit so small?
Due to its diminutive stature, the first H. floresiensis specimen
unearthed is thought by some scientists to be a diseased modern human. However,
multiple fossils with similar features have since been found.
Instead, it appears the hobbit may be an example of ‘island dwarfing’
– an evolutionary response that occurs when populations of large mammals become
isolated on an island with a limited food supply and a lack of predators.
A contradiction
H. floresiensis is a puzzling species. The very small brain size,
short legs, ape-like wrists and hipbone suggest it is more like an
australopithecine (a group living over 2 million years ago) than a human.
However, other parts of its anatomy suggest that it is a human species.
Archaeological evidence found in the same cave on Flores indicates H.
floresiensis may have used tools and even hunted and controlled
fire. Were their small brains somehow reorganised to allow for more
human-like behaviour? Or were early modern humans responsible for some of this
archaeological evidence?
Yet more questions
The discovery of H. floresiensis has raised many questions - not only
about this species, but about the human fossil record in Asia as a
whole. Stone tools dating back over 800,000 years have been found on
Flores, but we have no other evidence on the island of human evolution between
this time and the time of H. floresiensis.
Is this species a descendant of Homo erectus, who migrated out
of Africa into Asia? How did their ancestors reach the island of Flores?
Only modern humans are thought to make boats to purposely cross stretches of
water.
Did H. floresiensis and our species, Homo sapiens, ever
come into contact with one another? And what happened to H. floresiensis?
Was a volcanic eruption on the island the reason they became
extinct?
The discovery of this species highlights how much still remains to be learnt
about human evolution in Asia.
Denisovans
Denisovans,
together with Neanderthals, are our closest extinct relatives. They are
a recently discovered group of ancient humans from whom only a few fossil
fragments, dated to about 40,000 years ago, have been found.
Not only
did this group exist at the same time as modern humans, remarkable genetic
research has revealed that they interbred with some populations.
DNA evidence provides clues
In 2010,
scientists analysed limited DNA from a fossilised finger and a molar tooth
unearthed in Denisova Cave in the Altai Mountains, Siberia. The
initial research suggested they were from a genetically distinct group of
ancient humans that shared a common ancestor with modern humans (Homo
sapiens) and Neanderthals (Homo neanderthalensis) about 1 million
years ago. However, the whole Denisovan genome has now been reconstructed and
indicates a closer link to the Neanderthals.
Just as
remarkable was the discovery that the Denisovans, as this ancient human group
has become known, are related to a particular group of humans alive today –
Australasians, who live on some of the islands north of Australia and in
Australia itself.
Evidence of interbreeding
The study
showed that Australasians share around 5% of their genetic material with
the Denisovans. The most plausible explanation is that Denisovans were present
further south as well as in Siberia, and that they encountered and interbred
with pre-Australasian populations of modern humans migrating from Africa though
south east Asia around 60,000 years ago.
If the
populations were very small, it wouldn’t take much interbreeding to make a
genetic mark. As few as 50 Denisovans interbreeding with 1,000
pre-Australasians could result in their present-day descendants sharing 5% of
their genetic material with Denisovans.
Human evolution in Asia
Genetic
information suggests that Denisovans may have been part of the Homo
heidelbergensis lineage. In Europe, Homo heidelbergensis
gave rise to Neanderthals, in Africa they gave rise to us (modern humans), and
in Asia, perhaps to the Denisovans.
The link to this particular page found November 26, 2014 can no longer be located.
At this website by various means we seek to defend life, to encourage Christian faith, to promote Catholic tradition, to edify Marriage in its link to the Creator, to encourage families and individuals, and to support missionary disciples of Jesus. G.S.
----------------------------------------------------------------
© 2004-2021 All rights reserved Fr. Gilles Surprenant, Associate Priest of Madonna House Apostolate & Poustinik, Montreal QC
© 2004-2021 Tous droits réservés Abbé Gilles Surprenant, Prêtre Associé de Madonna House Apostolate & Poustinik, Montréal QC
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