Saturday 30 January 2021

Footprint on the Beach

Footprint on the Beach 

HERE is a nice story! A correspondent told me about it last night and it was on the radio news this morning. "A well-preserved dinosaur footprint has been discovered by a four-year-old girl on a beach."

And it was on Barry beach - not far from Bristol. It is now in Cardiff Museum and will, no doubt, be on display sometime soon. All you need to know is in the article.



Tuesday 26 January 2021

Dinosaurs - Fundamental Matters

Dinosaurs - Fundamental Matters 

THIS ARTICLE informed me about something I didn't know, that I didn't know - an unknown unknown. Unlike mammals who have two openings "down there" dinosaurs have only one! We have one for reproduction and one for expulsion of faeces. Dinosaurs and similar have a multi purpose opening called a cloaca.

This is not commonly found in the fossil record, but a chance encounter in a Frankfurt museum with psittacosaurus - a herbivorous dinosaur of labrador size, related to triceratops - gave the opportunity to study a cloaca more closely.

And the conclusion drawn was that the animals bottom was designed, among more prosaic functions, for display. Which gives me pause for reflection.


The fossil concerned


This discovery was part of the study of psittacosaurus. There is a very interesting video HERE which goes into some detail of how to make a dinosaur.






Sunday 17 January 2021

Where will your Electric Car really come from?

Where will your Electric Car really come from? 

A correspondent has brought this Bath Royal Literary and Scientific Institution lecture to my notice. It sounds rather interesting.

Where will your Electric Car really come from?


A study of the future availability of metals vital to emerging technologies

An on-line lecture by Professor Frances Wall of the Camborne School of Mines

 

Many countries including the UK have ambitious targets for a change from petrol and diesel vehicles to electric cars. The race is on, not only to get us to drive electric vehicles but to manufacture the cars and batteries. Other technologies such as wind turbines and a growing range of electronic devices are also needed for the sustainable society.  What is often forgotten is that the raw materials need to come from somewhere. New electric vehicles, and our other digital and clean technologies, need new metals. Not only do we need to find and mine enough of the technology metals like lithium, cobalt and rare earths, we need to make sure their production is contributing to sustainable development, not detracting from it.   

Professor Frances Wall is Professor of Applied Mineralogy, Camborne School of Mines, University of Exeter. She specialises in technology raw materials, especially rare earth elements, with interests in geology, processing, responsible sourcing and the circular economy. Frances has been leading two international consortium research projects on critical metals supply and now also leads a UK interdisciplinary Centre promoting the circular economy of technology metals. Frances was named one of the 100 Global Inspirational Women in Mining 2016 and awarded the William Smith medal of the Geological Society of London for applied and economic aspects of geology in 2019.

 

This on-line event takes place: 1st February 2021  7.30pm GMT

Book on Eventbrite £2 BRLSI members   £5 visitors:

https://www.eventbrite.co.uk/e/where-will-your-electric-car-really-come-from-tickets-135856433249

Footprints of Mass Extinction Survivor

Footprints of Mass Extinction Survivor

A correspondent has brought THIS ARTICLE to my attention. It is based on THIS PAPER which records the subject in great detail.

Tracks of the a creature were discovered in the Italian Alps, not far from the French border. And they were in rocks which have been assigned to the late Early Triassic. This is just after the Permian-Triassic mass extinction. At the time it was not far from the equator. And the temperature was rather hot.

They use photogrammetry to measure the tracks in exquisite detail.

The creature has been identified as being an archosaur - a terrestrial tetrapod but assigning a species to the trackmaker is rather difficult! But does not stop our authors! The give the tracks a name - Isochirotherium gardettensis - and then speculate that the track maker was a "a non-archosaurian archosauriform (Erythrosuchidae?)".

The main thing is that such a beast was there, so soon after the extinction event.


 

This is best seen as full screen - symbol at bottom right.

Mary Anning Statue

Mary Anning Statue 

You may know that there are plans to erect a statue of Mary Anning in Lyme Regis. A lot of money has been raised (including some of mine!) but they still need some more. If you are interested - and you should be - Go to THIS WEB PAGE and contribute. There is a very good short film to watch as well.


Denise Dutton’s preliminary sketch of how the statue will look.

Thursday 14 January 2021

Megalodon Teeth

Megalodon Teeth 

Megalodons seem to be flavour of the month! Following on from Monday's story we have THIS ARTICLE from Bristol University's School of Earth Sciences.

Megalodon means big tooth and the beast certainly had big teeth, unlike those of other earlier members of the group. This was thought to show that the species diet had changed - the earlier members had curved, blade-like teeth, Megalodon had broad triangular ones. Therefore, it was reasoned, the earlier ones used their teeth to pierce small and fast fish. Megalodon tore off chunks of whales and seals.

But this study, using finite element analysis (described in greater detail in THIS PAPER) shows that Megalodon's teeth were weaker than the earlier ones (allowing for the change in size). This makes a lot of speculation on dietary habits redundant.

And the change in tooth morphology is due to the great size of Megalodon.



Von Mises stress distribution plots in the anterior (Ant.), lateral (Lat.), and posterior (Post.) teeth of the five analysed otodontid species, simulating (a) puncture and (b) draw scenarios with scaled force magnitude. Mesial is left, distal is right. Arrows indicate loading points. Grey areas represent von Mises stress values higher than 5 GPa and 10 MPa in each of the scenarios, respectively.

Jet Stream History

Jet Stream History 

Where was the jet stream during the Younger Dryas? And how do you map it? And how does it matter? Read all about it HERE and HERE.

The Younger Dryas was a period of cooling at the end of the last glaciation - 12.9 to 11.7 thousand years ago. It would be no surprise if the jet stream had something to do with it but how do you map the jet stream?

Answer:- look at the glaciers of the period; identify the equilibrium line altitude (ELA) where ablation (mass lost) equals accumulation (mass gain); from that draw a map of precipitation across Europe 12,000 years ago. Simple! The sources tell you how to do it. 

Western Europe and the eastern Mediterranean were wetter than now. The bit in between was drier. And from this you can map the jet stream. 

Current computer models of the climate do not show this. To have confidence in predictions of future climate we need models which model the past with some degree of accuracy. Work such as described above helps in this.




Equilibrium Line Altitude  elevation surface for the Younger Dryas.

The ELA surface should be viewed as “theoretical” (ELAthl) because glaciers can only form where the topography is higher than the ELAthl surface. For example, there are no glaciers in SE England or the low countries. Black dots show the location of palaeoglacier reconstruction sites. The FIS and the West Highlands icefield are shown, but the ice mass in the Alps is not shown due to incomplete knowledge of its geometry at this time.

Monday 11 January 2021

Pregnant Megaladons - Avoid!

Pregnant Megalodons - Avoid!

If you can't find a scary dinosaur story a scary Megalodon story is almost as good! 

The source is THIS ARTICLE, referencing this ACADEMIC ARTICLE

Megalodons are extinct (thank goodness!) predatory sharks which grew up to 14 metres and died out about 3.6 million years ago. Being sharks, fossils are hard to come by as their skeleton is largely cartilaginous. But some parts can be mineralised and therefore preserved. Teeth (17cm.!) get a lot of attention but it is the spine which is the focus of the paper.

The vertebrae come from a specimen found in Belgium. X-ray scanning of the vertebrae revealed the internal structure and showed it to have growth rings, presumed to be annual. If so the beast died when it was 46 years old and was 9.21 metres long. The academic article details how this was worked out.

But what is fascinating is that it was 2 metres long at birth! And how did it get to be so big - by eating its siblings in the womb! It could not have been an easy pregnancy for the mother! (I may be projecting human values onto a shark in the last sentence. It was probably entirely normal for Megalodon mummies.)


Examples of examined vertebrae of Otodus megalodon (IRSNB P 9893). (a) One of the largest vertebrae (‘centrum #1ʹ) in IRSNB P 9893 (scale bar = 10 cm; photograph courtesy of IRSNB). (b) Computed tomographic image showing sagittal cross-sectional view of vertebra depicted in (a) (scale bar = 5 cm). (c) Computed tomographic image of sagittal cross-sectional view the largest vertebrae (‘centrum #4ʹ) in IRSNB P 9893 showing incremental grown bands presumably formed annually (* = centre of vertebra; scale bar = 1 cm)

Wednesday 6 January 2021

DOWN TO EARTH EXTRA - JANUARY 2021

 


DOWN TO EARTH EXTRA - JANUARY 2021

The latest edition of Down to Earth Extra is HERE.

And you can read it below.