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Cycads – early land plants near Grahamstown:

(External Link)

Forests of primitive plants such as glossopteris near mooi river and estcourt

Distribution of Glossopteris in Pangaea
Glossopteris

Near the end of the Palaeozoic Era, in the Permian period, Southern Africa had moved away from the South Pole. When the climate became warmer, the land becamecovered in new types of cone-bearing plants. The best known plant in the Southern hemisphere from that time is a tree called Glossopteris. Fossils ofGlossopteris tree trunks are common near Estcourt and Mooi River in Kwa-Zulu Natal. Plants like these formed the huge coal deposits that are mined in SouthAfrica today. The first true seed-bearing plants, which were simple conifers, appeared at the very end of the Permian Period.

Glossopteris and coal deposits:

(External Link)

Map of coal deposits in SA:

(External Link)

The coelacanth as a living fossil of the group that is ancestral to amphibians

The coelacanth is a “living fossil”; it is similar to 350 million year old fossils but is still alivetoday.http://www.flickr.com/photos/26573031@N05/2903081204/

The coelacanth is a lobe-finned fish from the Permian Period that was once thought to be extinct and was only known as a fossil. In 1938, a South Africanfishing boat netted a large fish with deep blue scales and fins on short “legs”. Professor J.L.B. Smith recognised it as a fossil fish fromrocks up to 350 million years old. It was thought to have been extinct for at least 65 million years. A second coelacanth was found in 1952 in the ComoresIslands. Many have been found since then. Another population has also been found near Sodwana Bay on the Kwazulu-Natal north coast.

See article at

(External Link)

Mammal-like reptiles in the karoo

Therapsid fossil in the Karoo (flickr)
Lystrosaurus (Wikipedia)

Reptiles diversified and spread as the most successful and largest land vertebrates in the Permian Period. One important group was reptiles with somemammal features that are called Therapsids. Thrinaxodon and Lystrosaurus were small therapsids that grew to about 50cm long. Fossils of these mammal-likereptiles have been found in the Karoo. These animals are seen as transitional between reptiles and mammals. They have several developmental advances such asextra ear bones and a bony palate, which are not normally found in reptiles.

Dinosaurs

Euskelosaurus browni

The special type of reptile called a dinosaur appeared and spread during the Triassic Period of the Mesozoic Era. A South African example of a dinosaur isEuskelosaurus browni. It was one of the first dinosaurs discovered in Africa. It lived in the area now called the Eastern Cape and fossils have been foundnear Ladybrand.

One of the best places in the whole world to look for dinosaur fossils is the sedimentary rocks of the Drakensberg Mountains and Maluti Mountains of southernAfrica.

Fossils of ferns and cone-bearing plants have also been found in the same areas as the dinosaurs.

First mammals

Megazostrodon – first mammal during the Jurassic period. Mammals could not dominate during the reign of the dinosaurs, as the dinosaurs were huge.(Flickr) (External Link)

The first true mammals appeared during the Jurassic Period of the Mesozoic Era. They were small, about the size of a mouse and lived side by side with thedinosaurs. South Africa is the only place in the world where there are fossils that show changes from the earliest Therapsid (mammal-like) reptiles from theKaroo rocks of the Permian Period to the first true mammals from the Drakensberg rocks in the Eastern Cape and Lesotho.

Early mammal evolution: Interactive site

(External Link)

Prehumans

Discovery of early Hominids in SA:

(External Link)

The Hominids are the “human-like” organisms that diversified from the apes. The apes lived in tropical forests, while the hominids lived inwoodlands and savannah. About 4mya, several different species of Hominids with large brains appeared in Africa. These prehumans are in the genusAustralopithecus. The modern human Homo sapiens appeared in Africa about 200 000 years ago and spread all around the Earth. Many people believethat the eastern side of Africa and South Africa are the original home of humans. The Cradle of Humankind at Sterkfontein and Kromdraai has yielded someof the most exciting and oldest hominid fossils in the world.

Ron Clarke with Little Foot and Mrs Ples. Both were discovered at Sterkfontein.

Activity: map key events in life’s history in southern africa

The text on the following pages describes some of the key events in Life’s History for which there is evidence in Southern Africa.

  • When you read each description in the text that follows, identify the places where evidence has been found and mark them on the map.
  • For each place you have marked, [provide a brief description of the event that happened]

Questions & Answers

is economics important in programming world?
Abdul Reply
What is oppunity cost
Kudzanayi Reply
it refers wants that are left unsatisfied in Oder satisfy another more pressing need
Osei
Thank bro
Kudzanayi
is the second altenative to foregone
swedy
How does monopoly and imperfect competion;public goods externalities ass symmetric information, ommon property ressourses; income distribution Merit goods and Macroeconomic growth and stability causes market failure?
Gcina
it is where by a labour moves from one place to another
Amoako Reply
yh
Osei
another
Amoako
yh
Osei
ok
Amoako
what is mobility of labour
George Reply
who best defined economics
paul Reply
what are the importance of economics
Adwoa Reply
answer
Asamoah
trade should be best
Aakash
help to know how our government operates in which system
swedy
1. To solve economic problems. 2. To predict economic event. 3. It also offer intellectual training to students.
samuel
How price elasticity can affect the markets of certain goods
Rhoda Reply
Heyy thanks for the teaching
Easter Reply
what is labour
Arthur Reply
Mental and physical ability of human being is considered as labour.
JEYARAM
and usually provided by human
KEMAWOR
is all human effort both physical and mental abilities to work
Asamoah
why is it that most countries in Africa abuse available resources
Okeoghene Reply
What is economics
Bright Reply
economics is a science which studies human behaviour as a relationship between ends, scarce means which have alternative uses.
prince
Why is scarcity a mind problem in economics
Alima Reply
because of the problem of allocation of resources
Osola
unequalled distribution of resources
Agyen
thanks
Alima
scarcity is a mind problem due to circumstances like when a particular product is demand in a high rate at the market.
Saihou
scarcity defines limited in supply relative to the demand them. so scarcity is a mind problem in economics because wants are unlimited while resources are also limited.
prince
it is a mind problem because it's one of the fundamental issue address by economics human wants are unlimited and resources available are limited this makes the study of economics essential
rashid
its a fundamental issue
zahid
it's not a mind problem, I think it's a economic problem, how to allocate scarce resources to satisfy need and want of society
Samiullah
Identify the different sectors in the economy
Moses Reply
what is economics
Moses
economic is study of human behaviour according to how they satisfie their numerous want
Osola
Economics is a science which studies human behaviour as a relationship between ends and scares resources.
JEYARAM
economic is study of human behaviour according to how they satisfie their numerous want
Amar
what is the law of demand
Adugbire Reply
the lower the price the higher the quantity demanded vice versa is true
Nadhin
yes
vivek
yes ooh
Asamoah
right
samuel
what are relationship between unemployment and economic growth
Weness Reply
no relationship
Awuah
When there is economic growth, there is increased opportunity in employment. When there is no economic growth mean there is recession causing a decline or downsizing in employment opportunities.
Teescou
unemployment or employment determined by the level of economic growth
Osola
why and for what was five kingdom of classification of organisms introduced
SUBHIKSHA Reply
give the ans as fast as possible
SUBHIKSHA
Comment on the ozone depletion over the period of 1982 to 1996
Mpho Reply

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Source:  OpenStax, Siyavula: life sciences grade 10. OpenStax CNX. Apr 11, 2012 Download for free at http://cnx.org/content/col11410/1.3
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