Two new species of Devonian tetrapods discovered in Eastern Cape

Dr Robert Gess from Grahamstown and Prof Per Ahlberg from Sweden

 

Dr Robert Gess of the Albany Museum in Grahamstown has discovered fossils of two unique tetrapods that will force a significant rewrite of the story of life in Africa during the Devonian Period, 360 million years ago.

The two new species, named Tutusius umlambo in honour of Archbishop Emeritus Desmond Tutu, and Umzantsia amazana to affirm its South African origin, are the only Devonian tetrapods ever discovered in Africa and the only ones ever found in what was once within the Antarctic Circle. They are a remarkable 70 million years older than any other four-legged vertebrates ever found in Africa.

The significance of this discovery lies in the place where they were found. When the four legged vertebrates paddled around the shallow lagoon, in what is now part of Waterloo Farm just outside Grahamstown, it was much closer to the South Pole than it is now.

Until this major discovery, palaeontologists had only found Devonian tetrapod fossils in areas that lay within the tropics during the Devonian period. These were the first four-legged animals, from whom all later four-legged animals, including amphibians reptiles, birds and mammals are descended.  Scientists therefore had good reason to believe that stem tetrapods evolved, and lived only in parts of our planet between 30 degrees north and south of the equator. At first these creatures probably still lived mainly in water but having developed legs and advanced air breathing they were later able to colonise the land.

Scientists assumed, based on the known fossil record, that vertebrates moved from water onto land (terrestrialisation) in the tropics and therefore attempted to understand the causes of this major evolutionary step by studying conditions prevalent in tropical water bodies.

Palaeontologists focussing on how certain fishes evolved the abilities to inhabit the land will now have to take into consideration the two tetrapods and their surroundings discovered on Waterloo Farm.

The approximately metre-long Tutusius and the somewhat smaller Umzantsia are both incomplete. Tutusius is represented by a single bone from the shoulder girdle, whereas Umzantsia is known from a greater number of bones – but they both appear similar to previously known Devonian tetrapods.

Gess says that when the tetrapods were alive, “they would have resembled a cross between a crocodile and a fish, with a crocodile-like head, stubby legs, and a tail with a fish-like fin”.

The evolution of tetrapods from fishes during the Devonian period was a key event in our distant ancestry. During the Devonian Period, tetrapods were largely aquatic so we can imagine that most of the time they swam or walked around in shallow parts of the estuary that was to become part of Waterloo farm.

Occasionally they may have left the water either to escape from a predator or to chase down some prey. It is also possible that they would have sought isolated pools where they could protect their young.

Their gradual transition to becoming land animals is pivotal to our existence because the basic tetrapod body plan – a spine with four limbs is the same design that has carried through to all four-legged vertebrates today. Indeed virtually every bone in our bodies can be matched back to one in these early creatures.

The descendants of stem tetrapods include all amphibians, reptiles, birds and mammals alive today. In some cases the front limbs of the animals have evolved even further so that the front legs of all birds and bats have been modified to form wings while human front legs are no longer used for walking. All us tetrapods are descended from the largely aquatic tetrapods that are found in the Devonian period, which already had four legs but which still had a finned tail.

Tetrapod expert gives a public lecture in Grahamstown

If we trace our ancestory back through time we rapidly reach our four-legged ancestors (or tetrapods). And if we follow that line far enough, say to 360 million years ago (in the Devonian Period), we meet ancestors who were also the ancestors of elephants, kangaroos, canaries snakes and all other land living creatures with backbones – some of whom have later lost their legs!  

 

Ahlberg came to South Africa at the invitation of local palaeontologist Dr Rob Gess to examine important new unpublished clues from shale deposits found at Waterloo Farm next to the N2 highway. 

He gave an informative lecture on the origins of Devonian tetrapods about 400 million years ago. The lecture entitled Devonian tetrapods, when, where and how was well received as it was crafted to be accessible to those who know little about palaeontology, yet interesting to the advanced enthusiast as well. 

Devonian tetrapods were strange four-legged animals that over millions of years made the transition from living in water to living on land. The word tetrapod means ‘four feet’ – so why do birds only have two feet and snakes have none? The answer is that the ancestors of both had four limbs, but in the case of birds, two of them evolved into wings while in the case of the snakes, all four limbs were lost in the process of evolution. 

Ahlberg explained to the audience how a group of large lobe-finned fish gradually transformed into a peculiar animal that looked something like a salamander and maybe behaved a little like a mudskipper. This, he said, was one of the most pivotal moments in vertebrate evolution, and ecological history – as the impact of their descendants on land ecosystems has been enormous.

He reviewed traditional thinking on the evolution of tetrapods and noted that developments in the last twenty years, including discovery of well-preserved intermediate forms,  have pulled the rug out from under dated text books - that often described fish dragging themselves onto land. Rather, tetrapods developed gradually within the aquatic realm, probably exploiting the shallows around lakes and lagoons.

Until very recently a series of forms from the Late Devonian of Europe, Greenland and North America (that formed a tropical landmass at the time) appeared to provide a neat sequence of forms, that illustrated a greatly improved textbook account of the emergence of legged vertebrates. Intermediate forms (or Élpistostegids’) had basic legs that still ended in fin webs rather than toes, lost their back fins and could move their heads like tetrapods. They had eyes on the top of their heads like alligators. Conveniently fossils of these creatures seemed to fall in age between those of conventionally fishy lobe-finned-fish, and the earliest tetrapods.

But as is often the case this neat new linear model has in turn been shaken up by new discoveries.
In the last five years, tetrapod track-ways from as early as the mid-Devonian have been identified in various parts of the world, indicating that known intermediate-type forms were living side by side with tetrapods.  In addition intermediate forms showing contradictory combinations of ádvanced’ and ‘primitive’ features have shown that the evolution of tetrapods is a lot more complicated, or ‘branchier’ than was earlier believed. 

Ahlberg said it was not always a straightforward exercise to tell which tetrapod or elpistostegid developed earlier or which came later because some species were advanced in one particular aspect while another species might be more advanced in completely different trait. It appears that the transition from fish to tetrapods was not an entirely linear progression. 

He said that as scientists now have a clearer picture of the morphological changes in the transition period, more questions remain to be answered. He also suggested that more intriguing creatures are still to be found that might help to answer these questions. 

Dr Gess has over the years discovered several remarkable fossils in the 360-million-year old black shale deposits he excavated from Waterloo Farm just outside Grahamstown. The fossils include, seaweeds and plants, a lamprey, a number of other fishes including a school of baby coelacanths and the pincer of an ancient scorpion. Per Ahlberg indicated that this site was unique for its age, a ‘lagerstatte’ in which the remains of an entire ecosystem are preserved.

Unlikely that Homo naledi lived alongside Homo sapiens

Prof Lee Berger’s announcement on Tuesday (9 May 2017) that the bones of Homo naledi have been reliably dated to between 236,000 and 335,000 years old is big news. It is also big news that his collaborators have found another chamber within the Rising Star cave system near Johannesburg containing yet more H. naledi  bones, including the almost complete skeleton of an adult male.

Narrowing down dates for the hominin fossils is remarkable because many palaeontologists, including Berger, had believed that based on their appearance, the bones were at least two million years old. If these estimates had proven to be accurate, it would have placed H. naledi  at the base of the Homo genus as one of the oldest species in our family tree.

The dating issue became controversial because the first bones were found in 2013 and presented to the public in 2015 without any evidence for their age. Some professionals insinuated that the absence of a reliable age for the bones showed that Berger and his team had rushed their investigations.

After a long wait, Prof Paul Dirks and his team published a paper this month in the online journal eLife showing that the concentration of radioactive elements and the damage they caused in three fossilized teeth mean that the fossils are most likely between 236,000 and 335,000 years old.

To ensure that the results were accurate, the paper confirms that “the most crucial tests were carried out at independent laboratories around the world, and the scientists conducted the tests without knowing the results of the other laboratories”.

The fact that the Rising Star fossils are much younger than had been expected does not necessarily mean that H. naledi  should be removed from the base of our family tree. It is possible that about 2.5 million years ago, there was a fork in the original family of H. naledi  where one part evolved into H. erectus and eventually H. sapiens, while the other side lingered on unchanged as H. naledi  for another two million years or so. 

While there is no evidence to support this possibility, it cannot be ruled out. It is quite probable that H. naledi  will turn out to be an evolutionary dead-end – an interesting one – but nevertheless quite dead.

However, what is likely to be the most controversial aspect of Berger’s announcement is his claim that “H. naledi  possibly lived at the same time, and in the same place, as modern humans”. This is the angle that led in most mainstream publications in South Africa.

The Port Elizabeth Herald declared unequivocally that “Homo Naledi lived with man” even though not a shred of evidence was presented to support this dramatic claim. The newspaper said, “About 300 000 years ago‚ South Africans shared their land with another human-like species: Homo Naledi”.

This statement created erroneous impressions that first of all, there were South Africans; and secondly that these South Africans lived in harmony with relatives of another species. We can almost imagine them breaking bread together and perhaps sharing a fraternal beer in the spirit of ubuntu.

News 24 online news site said, “scientists and researchers can now reveal that it is highly likely that the species lived alongside Homo sapiens” suggesting that they hung out together.

Even Wits Vice Chancellor Adam Habib got caught up in the political feel-good spin conjured up by Berger and according to the Herald said “The true significance of this research shows we belong to a common humanity. That is a fundamental thing.

“In a world of division … when people are looking at their ethnicity to define who gets what and in a world where we are becoming so intolerant of each other‚ this research shows we have very common roots. We represent a common humanity.”

Actually it doesn’t.

The real problem with portraying humans and H. naledi  as best buds is that there is no evidence to show that they were alive at the same time. If we take the youngest date for the existence of H. naledi  as being 236,000 years ago and the oldest date for anatomically modern humans as being 200,000 years ago – there is quite a large gap of around 36,000 years.

It is true that someone might find evidence to support the notion that H. naledi  is  younger or H. sapiens is older, but currently this possibility is not sustained. Things might change, but in terms of current research, Berger is stretching the boundaries of what might, conceivably be possible into the realm of what could be good publicity for his book - which coincidentally was published on the same day as his dramatic announcements.

Our house according to Google Street View

This is what our house looked like from Market Street before we got the new garage doors

The Origin of Humans Is Surprisingly Complicated - Scientific American

The Origin of Humans Is Surprisingly Complicated - Scientific American

Springvale Olive Farm - a great outing

Craig Rippon loves olives. He speaks about them with a passion that lights up his face and inspires visitors to buy armfuls of olive products before they leave his estate near Alicedale. Close to forty people joined the tour of Springvale Olive Estates at precisely 10.30 on Saturday morning at the start of a most enjoyable outing.

Rippon led the walking tour of the estate and did not stop talking about the different types of olives and their relative strengths and weaknesses for two hours.

First we walked across the main road linking the N2 to Alicedale and then huffed and puffed up the hill to see rows and rows of neatly aligned olive trees. Rippon has planted just over 7 000 trees of 12 varieties since he started the project in 2000.

Most of the time he talked about the Mission olives and the Manzanillas that the crafty Western Cape farmer surreptitiously slipped in among the Mission seedlings, but there were also the Kalamatas, the Frantoios and others with exotic sounding names.

One of the visitors asked Rippon what was his favourite type of olive – a question he was not able to answer because he says he loves whatever is being harvested at the moment. Why olives? After all the Eastern Cape is not known as an olive producing region. He explained that his family had bought the farm from the Wilmots in 1915 and ever since then his family raised sheep, cattle and sometimes even Angora goats. He realised however that stock farming was becoming ever more difficult in the area as game farming gained momentum.

The game farms allowed for the proliferation of small predators such as jackals that frequently took his lambs. As the predators lived in a conservation area it became increasingly difficult for him to protect his flocks. He said that his grandfather had at one time planted mielies on the farm but baboons helped themselves to his crops too often. On the other hand, olives that come straight off the trees have an unpalatable bitter taste so they are almost never stolen by people or animals.

Rippon has six permanent staff members and up to 40 seasonal workers who help him manage and harvest the olives. The groves cover roughly 34 hectares and can produce more than 100 tons of olives in a season. His best year was 2007 when he harvested just on 115 tons but the long drought that followed slashed production drastically and he was forced to pump his dams dry just to keep the trees alive. At the end of the tour, visitors were invited to taste the various types of olives produced at the estate, and of course everyone was trying to decide which type to buy and take home. Guests could then have lunch on the patio or a beautiful lawn outside the farmhouse.

Lea Davies from a farm in the Adelaide area and Lisa Mickelwright, a teacher at DSG, prepared the platters artistically made up of various types of olives, smoked ham and salami kebabs, cumin seed cheese, olive tapenade and grapes.

Clean air, a selection of Mediterranean style treats, a glass of wine and good weather made the outing a massive success for all concerned.

How secular are we in South Africa?

In recent weeks we have carried a number of letters and SMSes reacting to a Rhodes student who objected to the insertion of a Christian pamphlet in his student pack. The reactions have been quite varied – from people telling him to simply throw away the pamphlet without causing a fuss, to those who have supported his right not to be given religious material in a secular university, and of course there are those who have lampooned the entire debate with references to the Spaghetti Monsterists.

This newspaper has not formally taken a stand on whether we think it is acceptable to ply new students with religious material or not. Opinions in our newsroom are diverse, and we would probably not come close to consensus if we had an internal debate.

Nevertheless, if we consider the mandate of this newspaper to serve the community of Makana, we have probably done quite a good job on this issue. Grocott’s Mail has provided readers with a forum to exchange ideas on this issue.

The debate raises further questions about just how secular is our secular state after all? Most government schools in our area, and indeed, most schools in our country, base their values on a Christian framework, and at assemblies, songs sung by the whole school or by choirs, invariably have a Christian message.  

Zooming out to national level, whenever there is an important gathering of leaders; meetings invariably begin with a moment of prayer. Sometimes religious leaders of different faiths are also given an opportunity to say a prayer and then everyone stands up to sing our national anthem – God Save Africa.

Our coins do not claim, as US coinage does, that “in God we trust”, but at every turn, South African culture is rooted in Christianity. The two most important public holidays in this country – Easter and Christmas - are about the birth and death of Jesus Christ. Why then do we persist in describing our country as a secular state?

Perhaps we are in this situation because of a pragmatic inertia that discourages radical change, or perhaps our nominally secular state with some light religious trimmings is the model that South Africans prefer. 

Addo Elephant Park 2010 Oct 2

We made a family visit to the Addo Elephant Park on Saturday. It was wonderful and exciting. The last time we visited the park we saw no elephants at all, but this time we had three separate sightings.
At one of the water pans we saw a herd of about twenty elephants come to drink, play in the water, roll in the mud and then walk off.
We also had two sightings of lions - it was good but in both cases they were just lying around not doing much and they were quite far from the road.





It was a great opportunity to test my new lens (75 - 300mm) and we all really enjoyed ourselves.
On our first trip to the park last year we didn't see a single elephant, but as you can see from the photos above, we saw plenty this time.
Here is a short video clip of a lone bull elephant that was drinking at a pan. We watched him for quite a long time.

When we visited the park in April 2009 we we caught in a hailstorm and some flooding. Check the floods here.
Now compare how dry it is in October 2010 - watch this video below and see what bone-dry looks like.

Hope you enjoyed this page about our trip to the Addo Elephant Park.

Makana Amazing Chase

Fifteen teams set off on an Amazing Chase around the streets of Grahamstown this morning. Based on the idea of the TV program, the chase was designed to teach people a little about Grahamstown and at the same time generate some fun in the morning.
It was successful on both counts.
The Langs formed a team called the Colourful Crew based on our colourful tie-dyed T-shirts. As we are all very unfit we struggled to run from one station to the next, but we made it.
I think we are all going to be somewhat sore tomorrow.

A Call to Action: Working together to boost investment in African agriculture

By Steven Lang

An intricate array of interests is being woven together like fine Kente cloth at the African Green Revolution Forum (AGRF) in Accra Ghana this week. At least half a dozen heads of African governments, numerous international financiers and a wide range of NGO heavy-hitters are among the 800 delegates working together to find ways of boosting investments in Africa’s agricultural sector.

The conference is based on the precept that until the African continent is able to feed itself, it will always lag behind the rest of the world. Farming is the backbone of the continental economy, but it still requires considerable support for it to be able to feed its people. The aim of the AGRF is that not only should Africa be able to feed itself but it should also become the bread basket of the world.

This objective was stated in various forms several times during the opening addresses of the first session, but it was treated with a touch of scepticism by panel moderator Tumi Makgabo, who asked, “How can Africa feed the world if more than 300 million Africans go to sleep hungry every night?”

President of the International Fund for Agricultural Development (IFAD), Kanayo Nwanze, responded to the challenge saying that “Yes, we can – but the question is when”.

The conference is essentially about this – when can African small holder farmers turn the continent into the world’s breadbasket.
Almost all speakers in the opening sessions identified improving the “value chain” as central towards achieving this goal. This means that commercial value needs to be added at all stages along the extensive process of producing food.

In order for this to happen, governments need to create a policy environment conducive to attracting private investments. Private and institutional investors should be able to see realistic prospects of a return on their investments and the agricultural sector needs to change from subsistence to commercial farming. These goals and imperatives must be synchronised to work in harmony with each other so that all stakeholders can benefit. As Kofi Annan, chairman of the African Green Revolution Forum said, “Partnerships are crucial to success”.

There is broad recognition that Africa is not living up to its potential. Prime Minister of Tanzania Mizengo Kayanza Peter Pinda, described the continent as a sleeping giant. Quoting statistics from a report by the Sustainable Development Networks of the World Bank, he said that less than 10 percent of the 400 million hectares of the Guinea Savannah Zone is being utilised for agricultural purposes.

Peter Pinda stressed the importance of governments in creating the right environment for the Green Revolution and cited the example of Asia where increased food production played a critical role in driving the sustained economic growth of many countries in that region. He said, “Until African countries shape their own agricultural policies, based on their own realities, they will not be able to achieve a sustainable Green Revolution”.

The Tanzanian Prime Minister acknowledged the devastation caused by structural adjustment programmes in the late 1980s and early 1990s. International financial institutions imposed rigorous programmes on African governments in exchange for loans. He said that the result in Tanzania was a massive retrenchment of extension staff, the elimination of subsidies and curtailed funding for agricultural research and foundation seed farms. “The taps dried up, and so did performance of agriculture. The giant slept,” explained Peter Pinda.

Ghana’s Vice president, John Dramani Mahama, also referred to the damage caused by the structural adjustment programmes and described it as a tragedy “that it took us two decades to realise that we were wrong”.

Peter Pinda said that the abolition of input subsidies in the 1980s caused a collapse in fertiliser consumption in Tanzania from 142,676 metric tons in 1991/1992 to 77,557 metric tons in 2002/2003. His government took the decision to change this situation and in 2005/2006 introduced a voucher scheme that rapidly reversed the declining situation so that consumption increased to 260,000 metric tons in 2009/2010.

This dramatic increase in the use of fertilisers has resulted in a concomitant growth in food production so that even while facing serious drought in one third of the country, Tanzania is now able to feed itself and produce a surplus. Peter Pinda said, “The issue is now what to do with the bumper crops that we have produced this year”.

However, Kanayo Nwanze president of IFAD, made it very clear that simply increasing investments and making farmers more productive would not be enough to sustain the agricultural sector and enable the continent to feed the rest of the world. He said that farmers need storage capacity, access roads, means of transport, guidance on packaging and marketing as well as information systems to enable them to know about the best time to take their produce to market.

It is clear that all delegates at the African Green Revolution Forum have the same objective in mind – that is to vastly improve the production of the Agriculture sector in Africa. It is also apparent that there are few substantive differences on how to achieve this goal, therefore it should be reasonably easy to reach consensus at the meeting that Kofi Annan describes as “not a conference, but a call to action.”

Joburg Family 5 Sept 2010

I had just returned from a week in Ghana so on my way back to Grahamstown, I stopped for 24 hours in Johannesburg. First I went to 30 Cardiff Road where I met Angie and Sebastian who had spent a few days in Joburg because Sebastian is going to Saudi Arabia to teach music for two years.

Then I visited Ben Coetzee and we had a great braai with the Coetzee clan - it was great seeing everybody including Christopher and Candice.

Spent the evening back at 30 Cardiff Road with Herby, Avron, Barbara and Yael. It was really wonderful beign with family.

Visit to Addo Elephant National Park

While Angie and Mike were visiting us we decided to make a day trip to the Addo Elephant National Park. We took a slightly shorter route than the recommended but because we were in the bakkie it was not a problem going over the sand road towards Paterson.

From Addo Elephant National Park

Paterson looks like a really dead loss place - really not much going on there.

The actual trip to the Addo Park was just over 100kms to the gate.

It was a wonderful outing even though we did not see a single elephant. We knew they were around because there was an enormous amount of dung all over the place - but we did not get to see any of them.

It was a great day - great to be with my sister and great to have a really nice family outing.

Animals we did see:
Kudu - plenty both male and female
Warthog - lots, both male, female and babies
Black-backed jackal - two in separate sightings
Red Haartebees - only one
Cape Buffalo - a small herd of about twelve big males
Vervet monkeys - not actually in the park, just a few kilometres before
leopard tortoise
Blue crane - our national bird
Ostrich - quite a few
Red knobbed coot
Egyptian goose
Black-headed heron
Dung beetles - lots and lots of them as there was lots of poo

We were a little disappointed not to see the elephants but that is the luck of the draw.

From Addo Elephant National Park

From Addo Elephant National Park

After a brief refreshment stop at Addo Main Camp we drove along the Gorah Loop and to Carol's Rest where we came across the small herd of male buffalo.

From Addo Elephant National Park

We then returned slowly to the Zuurkop Lookout point where you can get out of your car, but there is a sign that advises you about lions.

From Addo Elephant National Park

We then had a picnic lunch that Ilza made back at camp.
In the afternoon we drove to the Kadouw Lookout point and along the Mbalala Loop. We later found out that other people had spotted elephants along this route, but we were not so lucky.
While we were are the park, there was a cloud burst with quite a lot of hail in some areas.

From Addo Elephant National Park

At one point near Hapoor Dam we had to make a choice between going down a dirt road, which was actually quite muddy, or going back along a surfaced road.
Fortunately I took the chicken option.
We returned on the surfaced road and then doubled back past the Gwarrie Pan to Rooi Dam where the dirt road would have met the surfaced road. The road was under a strong flowing stream - nobody dared try an cross it.

The cars on the other side faced quite a tricky journey back to the tar road, or they would have to wait it out.

It was a great example of a flash flood.
To see a map of the area we visited click here

Mila has a horror party

From Mila and Zoe Birthdays 2009

Mila had her party on the Saturday. She had a 'horror' theme so her cake was decorated like a bat and her friends came over dressed in black and wore witches hats etc.
In the evening they watched a horror DVD - Poltergeist. They screamed and stayed up very late, but it was all in good fun.
In this video taken quite early in the morning, she was opening a present from Aunty Debbie