Beasts before us is a great read

 

Bloomsbury Sigma 2021
ISBN 978-1-4729-8397-8

Elsa Panciroli is a young Scottish palaeontologist with a story to tell. She challenges the narrative that mammals were insignificant creatures living in the shadow of the dinosaurs until after the end-Cretaceous extinction.

The first age of mammals, she tells us, was in the Permian 300-250 million years ago. This is when the ancestors of therians were dominant and included large herbivores and carnivores quite as impressive as the later dinosaurs. Then there was another extinction event triggered by massive lava flows lasting 800 thousand years - The Great Dying. Those that survived were mostly small and included the first mammaliaforms. 

Yes, the definition of a mammal, especially in the fossil record, is based on us having only two sets of teeth with the deciduous teeth being lost at weaning. So for purists Elsa Panciroli is describing the history of the Synapsids, one of the two great lineages of amniotes, from which mammals arose. The other lineage was Sauropsids that comprises dinosaurs (including birds) and reptiles.

In Pursuit of Early Mammals

The history of synapsids has been told before but in a more academic style by one of Panciroli's heroines Zofia Kielan-Jaworowska (review here). 

Some mammalian features undoubtedly evolved earlier than lactation. They include fur and differentiation of the teeth into incisors, canines and molars. The immediate ancestors of therians adopted a nocturnal life style. There is evidence for this in the structure of our eyes (two of the four types of cone in other vertebrates were lost) and most mammals have poorer colour vision than primates where it has been partially regained through evolution of opsins. 

Elsa Panciroli started this book while finishing her PhD studying Jurassic fossils from the Isle of Skye. A truly astonishing achievement. The account of synapsid evolution alternates with trips to the field, scanning of fossils embedded in rock using the synchotron near Grenoble and (carefully supervised) viewing of rare Chinese fossils. 

Zofia Kielan-Jaworowska in the field

Panciroli is also very much of her time. She laments that many key fossils were taken without consultation of indigenous people. It concerns her that most palaeontologists have been male (despite Kielan Jaworowska see here) and of course she worries intensely about climate change. In a final short chapter she speculates on what type of mammal will surive the current mass extinction.

Ingeborg Rapoport: a pioneer in perinatal medicine

Professor Ingeborg Rapoport (second from left) 1985
Bundesarchiv CC BY-SA 3.0

The third season of Charité takes place in 1961 during erection of the Berlin Wall. Several of the characters are based on real life persons the most striking being the pediatrician Dr Ingeborg Rapoport. She later became the first Professor of Neonatology in Germany. Indeed one of the central themes in the television series is the conflict between pediatrics and obstetrics about care of the newborn. Obstetrics is here represented by Professor Helmut Kraatz.

Ingeborg Syllm was born in German West Africa (Cameroon) in 1912. She was raised as a protestant yet denied completion of her medical degree when the NSDAP came to power because her mother, a concert pianist, was Jewish. In 1938 she moved to the United States where she completed her medical education and specialised in pediatrics. In 1944 she married Samuel Mitja Rapoport a physiological chemist who had left Austria after the Anschluss. They were to raise four children.

Both the Rapoports were members of the Communist Party and had to flee again in the 1950's when under investigation for un-American activities. They finally settled in Berlin and remained in the DDR after the wall was built.

Ingeborg Rapoports autobiography

In 1969, just before the retirement of Kraatz, Ingeborg Rapoport was elected to the first Chair of Neonatology in Germany. She herself retired in 1973 but remained active, publishing her autobiography Meine ersten drei Leben (My First Three Lives) in 1997.

In 2015, when the University of Hamburg offered her an honorary doctorate in lieu of that denied her in 1937, she asked instead leave to defend her thesis and passed the oral examination with magnum cum laude. Ingeborg Rapoport was then 102 years old. She lived to be 104.

Professor Sauerbruchs Placenta Cream

 

Ad for Hormocenta from Professor Sauerbruch

The second season of Charité about the famed Berlin hospital revolves around the character of Ferdinand Sauerbruch the leading surgeon of his time (brilliantly portrayed by Ulrich Noethen).

His second wife Margot (née Grossman) started to read Medicine after leaving her second husband and then served an internship at Charité where she met Ferdinand. They were married in March 1939. In addition to practising medicine Margot was a businesswoman. As managing director of Pharmazeutischen und Kosmetischen Präperate Böttger Gmbh she marketed a popular skin cream based on a placenta extract. Her famous husband's name featured in the advertisements.

Ad for Hormocenta featuring the
actress Marika Rökk

Placenta extracts in cosmetics were more widespread than I had supposed. Many were based on placental extracts and amniotic fluid of cattle (see here). 

The Surgeon (Ferdinand Suaerbruch)
by Max Lieberman (Wikimedia Commons)

I am watching Charité on Danish television but the first two seasons are available on Netflix. The first season features such luminaries as Rudolf Virchow, Robert Koch (Nobel Prize 1905), Emil von Behring (Nobel Prize 1901) and Paul Ehrich (Nobel Prize 1908). 

Land bridges to Madagascar

 

Sweepstakes distribution as envisaged by G. G.Simpson

One of the first posts on this blog (here) was about sweepstakes distribution as proposed by George Gaylord Simpson. Simply put it envisaged that animals endemic to Madagascar, such as lemurs and tenrecs, as well as now extinct hippopotami, crossed the Mozambique Channel on rafts of vegetation. 

This has been widely accepted and bolstered by evidence that ocean currents in the Cenozoic might have been more favourable to rafting than they would be today (here).

Now a cross-disciplinary group has taken a fresh look at the question and reached quite a different conclusion (here). They begin by questioning whether small primates or tenrecs could survive on the crossing which they estimate could take several months. Further they dismiss the idea that a hippo could swim to Madagascar; their arguments on this point are convincing. Could a raft be strong enough to support a hippo during the crossing (as pictured in the cartoon above)?

Verreaux's Sifaka (Propithecus verreauxi)

They suggest that there has been too much focus on the width of the Mozambique Channel and not enough on its depth. They present a mass of data, bewildering to me, but supporting the possibility of land bridges from Africa to Madagascar. The first of these at the Cretaceous-Palaeocene boundary might have been used by the ancestors of lemurs and tenrecs (their African cousins are lorises and otter shrews).

A land bridge at the Eocene-Oligocene boundary could have been used by the ancestors of Malagasy rodents and Malagasy carnivores such as the fossa. Finally there was an incomplete land bridge at the Miocene-Pliocene boundary that might be a more plausible route for a hippopotamus to cross.

The obvious question is why the Malagasy fauna is so depauperate. Why are there no monkeys, large cats or ungulates? The authors suggest they may have made it to Madagascar but gone extinct. Fortunately for this argument, the fossil record on Madagascar is very poor.

And what about that other discussion of land bridges versus rafting - how did hystricognath rodents and the ancestors of Neotropical primates reach South America (see previous post)?

The Sediments of Time - Book Review

 

This account of Meave Leakey’s search for human ancestors in the Turkana region of Kenya is at once intensely personal and scientifically sound.

Born Meave Epps in 1942 she read marine biology at Bangor but found herself without a job because research ships lacked facilities for women. On a whim she answered an advertisement by Louis Leakey who was recruiting for a primate research centre in Kenya. Once there she soon found herself looking for hominin fossils with Louis’s son Richard whom she later married. Their life together was full of drama as Richard suffered both kidney failure and the loss of his legs in a plane crash.

Reconstruction of Homo rudolfensis
(KNM-ER 1470) discoved by Meave Leakey 
Photo byy Don Hitchcock CC BY-SA 4.0

Meave soldiered on and discovered or co-discovered significant specimens of several hominins ranging from australopithecines through early members of our genus (above) to Homo erectus. The first part of the book details this story and gives a fascinating account of work in the field (with no facilities for men or women!) and the ever present need to find fossils attractive enough to ensure continued funding. In the second part the emphasis shifts towards putting individual fossils in the context of work by others (including mother-in-law Mary Leakey) and painting a broader view of human evolution. The final part continues the story of exploration while explaining the changes in biology that led to evolution of our species.

Meave and Richard had two daughters. Louise followed in the Leakey family business of finding fossils while Samira co-authored this book. One chapter considers the importance of grandmothers for human reproduction and indeed there are grandchildren. Who knows if a fourth generation of Leakeys will search for clues to our past?

There are excellent photos from life in the field and some very useful line drawings. But surprisingly few photos of the fossils themselves. That is really my only criticism of an excellent book. I found it useful to have the well illustrated book Our Human Story to hand as a complement to the text (reviewed here).

Arsenic and old lakes

Microbial Mats (purple) at Laguna La Brava Chile
From Visscher et al. 2020 CC BY 4.0

Atmospheric oxygen was not plentiful until the Great Oxidation Event yet life appeared much earlier during the Archean Eon (more than 3 gigayears ago). One suggestion has been that  arsenic acted as an electron donor to drive photosynthesis in early life forms.

A new paper by Visscher et al. shows how this might have worked. They investigated microbial mats from Laguna La Brava in northern Chile. These survive under hypersalinic and anoxic conditions by using arsenic and sulphur as electron donors.

A parallel is drawn with the Archean lakes of the Tumbiana Formation where lithified microbial mats are found. 

Kindred or cavemen

 

Neanderthals gained prominence in the Eemian interglacial some 130 thousand years ago and survived several cold and warm periods before disappearing 40 thousand years ago. So they have a much longer history than modern humans. What were they like? Becky Wragg Sykes gives some answers and where answers are missing supplies well argued speculation. Often speculation is backed up by comparison with recent human hunter-gatherers.

The strength of this book lies in covering so much ground. For example I have followed the ancient DNA closely, know a bit about fossil finds, but have steered clear of lithics (e.g. bifaces formerly known as stone axes). Yet there are so many more of these remains and new methods to get the most out of them. They are key to understanding the Neanderthals skills and way of life.

Importantly Neanderthals did not just huddle in caves between hunting woolly mammoths. They also lived through warmer periods and hunted horses and other prey. They were geographically diverse too living in the warmer climes of Iberia and across Asia to the Altai mountains in Mongolia.

It is common knowledge that Neanderthals mated with humans and with the enigmatic hominins called Denisovans about whom we know very little. Sykes thinks they may have been so like us that sex could have been consensual. She is a great fan of Jean Auel (whose books I too have read).

My enthusiasm waxed and waned with every chapter. I could not quite get accustomed to the author's style of writing. Apart from lithics I did not learn an awful lot. But perhaps the book was not written for me.

This one was more my style.