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NOVA programs on PBS are usually very informative and very well produced. This link is will worth following to explore the online resources associated with the program.

There is so much information available on the web and in the library concerning the evolution of mankind. when preparing this course, I must have visited hundreds of sites and looked at some 20-30 books. This site stands out as an example of the very effective use of webs design and multimedia. I was also very impressed by this PBS production especially the interactive time line.

I really miss watching the BBC Horizon series each week. These programs are so well produced. They are intended for an informed and critical audience, who are able to follow an detailed argument and are not afraid to ask some pertinent questions. The two programs we looked at in class, “The day the Earth nearly died” and “What really killed the dinosaurs?” are some of the best productions I have seen that deal with Earth Science (my favorite is “Supervolcano“).

We often watch natural history programs on TV, often on the Science, National Geographic, or History channels with less than a fully critical eye.

I have been a Fellow of the Geological Society of London for 23 years, and so I just had to let you all read this recent statement.

A Statement by the Geological Society of London

Approved by Council 10 April, and published 11 April, 2008

“Young Earth Creationism”, “Creation Science and “Intelligent Design”

This Society upholds the right of freedom of belief for all. The freedom scientists enjoy to investigate the nature and history of the Earth is the same freedom that allows individuals to believe – or not – in a deity.

Science’s business is to investigate the constitution of the universe, and cannot pronounce on any concept that lies “beyond” nature. This is the meaning of "agnostic", the word coined by former GSL President Thomas Henry Huxley, to describe a scientist's position of being "unable to know". This Society has therefore long operated according to the view that religion and science only become incompatible with each other when one attempts to trespass upon the domain of the other.

The idea that the Earth was divinely created in the geologically recent past (“Young Earth Creationism”); attempts by Young Earth Creationists to gain acceptance for what they misrepresent in public as corroborative empirical evidence for this view (“Creation science”); and the allied belief that features of the universe and of living things are better explained as the direct result of action by an intelligent cause than by natural processes (“Intelligent Design”), represent such a trespass upon the domain of science.

The Geological Society of London is the oldest national learned society for the Earth sciences in the world, and embodies the collective knowledge of nearly 10,000 Earth scientists worldwide. On their behalf it wishes, during the United Nations International Year of Planet Earth, to place on record the following facts as being long established beyond doubt.

• Planet Earth, along with the other planets in the Solar System, was formed approximately 4560 million years ago.
• Life has existed on Earth for thousands of millions of years. It has evolved into its current form by a combination of genetic variation and natural selection – and is likely to go on doing so for as long as it continues to exist.
• Close study of the structure and organisation of living animals and plants clearly indicates their common ancestry, and the succession of forms through the fossil record, as well as the genetic record contained in every living organism, provides powerful evidence of the reality of evolution.

Further information

• For a statement on this subject by the Royal Society, the UK national academy of science, go to http://www.royalsoc.ac.uk/news.asp?year=&id=4298
• For a recently updated (2008) version of the US National Academy of Sciences booklet Science, Evolution and Creationism, go to: www.nap.edu/sec. This document will tell you what is and is not science, summarises the scientific evidence for evolution by natural selection, and highlights repeatedly how leading religious figures have spoken out in favour of evolution as being consistent with their world-view.
• For a statement on Intelligent Design issued by the International Society for Science and Religion, the main academic international society dedicated to the relationship between science and religion, see www.issr.org.uk/id-statement.asp.
• For an account of evolutionary knowledge, see vertebrate palaeontologist Prof. Kevin Padian’s evidence, given in trial (Kitzmiller v Dover): http://tinyurl.com/2nlgar. This destroys the bases of young-Earth creationists’ assertions regarding critical gaps in the fossil record.
• For a clear account of evolution given by one of the world's leading geneticists, showing how it is compatible with religious belief, see The Language of God by Francis Collins (Free Press, 2006). Francis Collins is Head of the Human Genome Project.
• Alexander, D. & White, R. S. (2004). Beyond Belief: Science, Faith and Ethical Challenges, Lion, Oxford, 219pp. Gives an accessible account of science and its interaction with religious views, including sections on evolution (with a critique of intelligent design), the age of the Earth and global environmental issues.
• Gould, Stephen J. 1999. Non-overlapping magisteria. A succinct and entertaining exposition of the lack of conflict between science and non-literalist religious thought. Published in: Leonardo’s Mountain of Clams and the Diet of Worms. Jonathan Cape, pp269-283.
• Pope Pius XII 1950, Papal Encyclical Humani GenerisENDS

So many students get interested in natural history through the Science Channel, Discovery Channel or National Geographic Channel. I like to use clips from these films to illustrate aspects of earth science that can be on the “dry” side without good visuals. There are always the thorny questions of how well these films represent established scientific opinion, and (not least), are they even right on the basic facts. I have listened to too many earth science films tell me that the Earth’s mantle is molten (it is not) to believe in the facts without further proof. I advise you all to take what you hear/see in these films with a proverbial pinch of salt! Nevertheless the BBC have a better than average reputation for getting their facts in order, and with some small exceptions, such as the early appearance of gymnosperms, the series we watched, “Walking with Beasts” is one of the best examples of its kind. Beyond “fact-checking” it is also important to analyze critically what is based on solid fact, and what is reasonable deduction. Beyond this we enter the cloudy realms of supposition and speculation. Viewer beware! This film is full of examples of clear and cloudy reasoning, and your task was to determine which of the many claims fall in which category.

We had a discussion about the origins and classification of the Glossopteridales. The debate was whether they belonged to the Gymnosperm group or to the Pteridosperm group of plants. The web sites below show that there is a difference of opinion. You will find more references to their Pteridosperm affinities (based on the fern-like sporophyte structures on the leaves) than to their Gymnosperm affinities (based on broader characterisitcs such as overall form and structure of the bole (trunk). The distinction is beyond the level of the class, but does serve to illustrate the confusion that can arise with fossil plants of uncertain origin and with characteristics that do not fit neatly within existing classification schemes.

Brittanica:

Long considered a fern after its discovery in 1824, it was later assigned to the gymnosperms. It is regarded by some authorities as being close to the ancestral angiosperm, or flowering plant. Certain poorly preserved reproductive structures associated with the leaves may in fact be the seed-bearing capsules of Glossopteris. Glossopteris is the key plant in a fossil assemblage called the Glossopteris flora, which also includes several related fossil genera (e.g., Lidgettonia and Gangamopteris) in Late Paleozoic rocks of South Africa, India, Australia, and South America.

Wikipedia 

Long considered a fern after its discovery in 1824, it was later assigned to the gymnosperms. The genus is placed in the division Pteridospermatophyta. In reality, many of the plant groups included within this division are only distantly related to one another.

University of Berkeley 

The reproductive structures of glossopterids are as unusual as the foliage leaves. They appear to have been borne on leaves as in other “pteridosperms“. Poor preservation has led to much controversy over their structure and their arrangement on living plants from which they came. At least one point has become clear: pollen and seeds were produced in different organs, attached to separate leaves, though the specifics of the organs themselves are not as clearly settled. Pollen organs have been described as anything from a modified leaf bearing stalked pollen sacs to cone-like clusters.

Week Ten Presentation

The presentation from this weeks class. I hope you enjoyed Dave Hutchinson’s presentation of his selection of fossil plants. This was an excellent and truly representative presentation with some really special samples that you would be hard put to find in a good museum.

Introduction to Plants

This week we are going to look at modern plants, plant reproduction and ecology before looking at the geological evolution of plants and plant fossils next week. You can find the PowerPoint for this week by clicking on the title of this blog.

You will probably find this article hard to follow until we have gone over some of the material to be covered in class. This is an article by Paul Kenrick and Peter Crane that was published 10 years ago in the Journal Nature. Lots has happened over the last 10 years, but this is still a good introductory paper. Do not expect to understand every biological term that you come across in the paper, rather focus on the main themes.

The origin and early evolution of plants on land

Cambrian Explosion

Read this over the weekend and tell me what you think about it. People who see this an let me know by adding a comment will get some extra marks.