Planet Earth - Devonian Period

The Devonian Period ran from 416 to 359 million years ago. Details to come...

Planet Earth - Silurian Period

The Silurian Period ran from 444 to 416 million years ago. Details to come...

Planet Earth - Ordovician Period

The Ordovician Period spanned from 488 to 444 million years ago. The biodiversity of the marine life continued to expand, especially in the shallower seas where organisms that used calcium carbonate in their shell, with such appearances of arthropods and molluscs. The period also saw the first vertebrate (species with a back bone) family start, namely the fish and some with jaws that evolved in the latter part of the period.  

There were higher sea levels in the Ordovician and at the start period, from around 480 MYA, the climate was very hot due to high carbon dioxide levels within the atmosphere - an early example of the Greenhouse Effect - which led to a potential sea temperature of 45 degrees Centigrade. These levels of water temperature may sound wonderful but it reduced the biodiversity of the more complex (multi-cellular) organisms.

By 460 MYA, the sea temperature had reduced to the types of temperature found in the current equatorial seas. The shallower seas became more inhabited by organisms that exploited the calcium carbonate present in the sea to provide more elaborate shells and body parts. Just think of that, the next time you see a crab, lobster or oyster in the fishmongers.

The marine faunal (means animals) life of this period included some communities of suspension feeders in tiers, which led to the basis of a food chain that still exist today. It is thought that the diversity of marine faunal organisms that share similar characteristics increased fourfold (Dixon, Dougal; et al. (2001) Atlas of Life on Earth. New York: Barnes & Noble Books pp 87)  as well as an increase in filter feeder organisms. The creatures that were typical of the Cambrian period - the archaeocyathids, the eocrinoids, the inarticulate brachiopods, the trilobites were succeeded by the articulate brachipods, the cephalopods and the crinoids by the middle of the Ordovician period. It was also a good time to start scuba diving, if such a thing had been invented, as coral species that create reef-like structures were taking advantage of the calcium carbonate in the water.

But life on the land was restricted to the bryophytes and a few fungal structures (Arbuscular mycorrhiza) that made nutrients more readily available to plant cells - there have been fossils found of hyphae and spores from around 460 MYA.

Planet Earth - Cambrian Period

The Cambrian Period ran from 542 to 488 million years ago. Not literally ran. The period is the first period of the Paleozoic Era. The best place to look at Cambrian rock examples is in wales, the Latin for Wales being Cambria. This is also where Alec Amos, past Whatlington village members, moved to after leaving the village. He and his wife worked hard especially for the village hall and he was the originator of the Whatlington Duck Race at the Village Fete on the River Line.

Back to the Cambrian rocks and due to their age and their structure being altered through metamorphic movements, it is quite hard to comprehend their specific geographic reconstructions. However, it is purported that Pannotia, a super continent, was breaking up early in the Cambrian period with other smaller land masses (Baltic, Laurentian and Siberia) having calved from Gondwana's super continent. It is thought that most land masses were in the southern hemisphere in the early Cambrian with a slow migration of continents towards the northern hemisphere during the latter part of the Cambrian period.

The land was mainly desert-like with potential microbial mats of algae, fungi and lichens. However, with the reduction in the quantity of sea ice in the Cambrian period, there was a rise in the sea levels and thus shallower seas formed around the edges of the land masses.  This period saw an increase in aquatic biodiversity, despite the disappearance of of animals that relied upon microbial mats on the sea floor. These mats were destroyed by the increase presence of burrowing animals. The greater an animal's ability to adapt increases its success to taking over a new ecological niche. Similar to business today.

There is evidence for species becoming more mineralised. The process through which an organic substance becomes impregnated by inorganic substances - for example a bacterium may use the organic part of matter thus leaving the waste minerals within the body. This process aided the preservation of fossilised records of life. However at this time, the mineralised species were found at the benthic level of the sea, the lowest part of the sea, in the water column and the Cambrian fauna lived on or above the sea bed.

Planet Earth - The Ediacaran Period

The last period of the Neoproterozoic Era, it ran from 630 to 542 million years ago and named after a South Australian range of hills (where some fossils of the Edicaran period were found in 1946). This period had few faunal fossils as animals had yet to form hard shells. But it does record the oldest definitive multicellular organisms with tissues - the most regular examples being segmented worms. This site gives an introduction to Ediacaran fauna.

Whatlington News Readers

Welcome to this blog or online resource to both Whatlington and Vinehall Street's history. As you may have noticed from the titles of other posts that you can see to the right of this panel describe some times past. If you go far enough back, you will see some memories of both villages. I then decided to go back to the beginning of time, as much as Science can tell us. I am in the process of adding titles to the periods up to the current day so that They can be added to in greater detail later on. If you have some archival material that you would like to add, please leave me a message at wvarchive@hotmail.co.uk and I hope to bring us to date very soon, all the best and have a lovely day.

Planet Earth - The Cryogenian Period or Snowball Earth

Apologies for the delay in rebooting the Whatlington and Vinehall Street Archive,this posting describes a period when the planet's surface was covered in snow and ice is written at the same time the village has entered a period when the snow and ice has covered much of the Whatlington and Vinehall Street. 

The Cryogenian period combines the two Greek words for both "ice" and "birth" and it suggests that this period that ran from 850 to 630 million years ago. Within these 220 million years, the Earth had to deal with two glacial periods - the Sturtian and the Marinoan - where the glacial work extended to the the equator.

It is possible to record the work of erosion by ice (glacial erosion) by studying the palaeo-landscape and the debris left by the glacial retreat (the warmer climate melts the ice). These deposits have been found in Australia, China, Congo, Ireland, North America, Norway, the Sahara desert and Scotland.

The Sturtian glacial period is estimated to have run from 750 to 700 million years ago, whereas the Marinoan (also known as the Varanger - named after the Norwegian fjord where tillite (glacial deposit) was found by Reusch in 1891) ended in ??

There are several mdoels or hypotheses that suggest the potential process or cause for the initial conditions for the model of Snowball Earth (they can be found here of which I have summarised below):

Williams (1975) proposed that the angle of the Earth's orbit was greater than the present angle; if the angle were greater than 54 degrees, the energy from the sun would heat the polar regions more than the equator and potentially allow glaciers to form around the equator. The Milankovitch cycle, named after a Serbian civil engineer and mathematician, suggests that a global wobble of a few degrees over a period of tens of thousands, but not tens of degrees. A study of stromatolites (remember those?) in the 1980's suggest that the angle of the Earth to the sun was within its present limits.

Another model suggested that the sun's heat was less than today due to the maturation of the sun, this may have led to the planet more susceptible to global freezing and despite an early glacial period, the Huronian glaciation in the Siderian Period, it does not suggest why more glacial periods did not occur previously.

There are more three more theories that range from a change in the sea levels that affected the global energy budget; the global location of the continents around the equatorial region that led to a change in the carbon dioxide levels in the atmosphere; even the break up of the supercontinent Rodinia may have led to Snowball Earth.

Equally, there are a similar number of theories that led to the melting of the two glacial periods and these can be found here.