from the world's big
The Sahara is a harsh environment today. It used to be much, much, worse.
- A new study compiles a comprehensive record of a fossil-rich area of southeastern Morocco.
- Giant swimmers in a long-gone river system fed huge terrestrial and flying predators.
- The area was home to a diverse population best studied from afar.
Set the Wayback Machine to 100 million years ago. Where do you want to go? Well, where you really don't want to go is the Sahara. According to the lead author of a new study of Cretaceous rock formations in southeastern Morocco, the region was "arguably the most dangerous place in the history of planet Earth, a place where a human time-traveller would not last very long."
A ferocious, ravenous community
Geographical setting of the Kem Kem region and outcrops
Image source: Ibrahim N, Sereno PC, Varricchio DJ, Martill DM, Dutheil DB, Unwin DM, Baidder L, Larsson HCE, Zouhri S, Kaoukaya A.
The paleontologist/comparative anatomist quoted above is Nizar Ibrahim of the University of Portsmouth in the U.K. The rock formation he and his colleagues mapped has been known as the Kem Kem beds, and it reveals a very different Sahara than we know today. The study proposes rechristening the sites as the "Kem Kem group," incorporating two distinct formations: the Gara Sbaa Formation and the Douira Formation.
100 million years ago, a massive river system ran through the area. It was home to some absolutely massive theropods, including the fearsome saber-toothed Carcharodontosaurus, which measured over 8 meters in length. The giant carnivore had huge, powerful jaws with long — up to eight inches — serrated teeth. There was also the fleet-footed Deltadromeus — which means "delta runner" — and various large-bodied pterosaurs screaming down from the skies to grab prey.
The prey was enormous, too. Fish that lived in the river system included lungfish and prehistoric coelacanths, some "four or even five times as large as today's coelacanth," according to co-author David Martill. Then there was the Onchopristis, a freshwater hark with deadly rostral teeth, "like barbed daggers, but beautifully shiny," he says, as well as a nightmare full of large crocodyliforms.
The study sums it up: "No comparable modern terrestrial ecosystem exists with similar bias toward large-bodied carnivores."
A paradoxical site
Example Kem Kem localities
Image source: Ibrahim N, Sereno PC, Varricchio DJ, Martill DM, Dutheil DB, Unwin DM, Baidder L, Larsson HCE, Zouhri S, Kaoukaya A.
The Kem Kem group is comprised of exposed fossils on the face of a long-winding escapement near the Moroccan-Algerian border, at the northwestern edge of the Sahara Desert. The beds are fossil-rich and are more accessible (and the fossils themselves more exposed) than at other such sites in northern Africa. Similar fossils have been found by other researchers in the western desert of Egypt, as well as in the northern and central Sahara. The most recent calculation of the fossils' age is that they hail from the late Albian-early Cenomanian.
One of the site's most interesting characteristics, of course, and a source of some controversy, is that it contains both continental and marine species. Therapods are also represented to an unexpectedly large degree. Some have suggested the fossils come from two different, overlaid environments from two different periods. Others are troubled by the large number of incomplete specimens. The study, however, assumes the river-system view.
Collection of Kem Kem fossils has been going since at least the 1940's, and many have found their way into collections around the world. As part of this study, Ibrahim visited these far-flung specimens across several contents. Some of the fossils are well-documented, and some have uncertain provenances, making the task of constructing a cohesive, accurate picture of the site a challenge. Still, says Martill, "This is the most comprehensive piece of work on fossil vertebrates from the Sahara in almost a century, since the famous German palaeontologist Ernst Freiherr Stromer von Reichenbach published his last major work in 1936."
O.T. Olsen's gorgeous 'Piscatorial Atlas' (1883) describes a world now destroyed and forgotten
- In little more than a century, fish stocks in the North Sea have declined by 99%.
- For people living today, a grey and exhausted sea is all they know.
- O.T. Olsen's Atlas of the North Sea's fish species is a reminder of the richness that once was.
"Specialist and magnificent"<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yMzE1OTM3Mi9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTYzOTM0MzMzMX0.PkQGcBkP0cmequpopd2aYgZJizI7c0emU37M_iXFwEE/img.jpg?width=980" id="6c165" class="rm-shortcode" data-rm-shortcode-id="43899a08c2e50c095db89f66e1919b99" data-rm-shortcode-name="rebelmouse-image" alt="In red, an oyster bank the size of Wales, between the Dogger Bank and the coast of northern Netherlands." />
In red, an oyster bank the size of Wales, between the Dogger Bank and the coast of northern Netherlands.
Image: Wellcome Collection. Public domain.<p>Ole T. Olsen's 'Piscatorial Atlas' is a masterclass in data presentation, and it doesn't half look bad either. As <a href="https://bryarsandbryars.co.uk/whats-that-got-to-do-with-the-price-of-fish-ole-theodor-olsens-piscatorial-atlas/" target="_blank">map guru Tim Bryars says</a>: "The late nineteenth century was the heyday of the thematic atlas, but I have rarely seen one quite so specialist or as magnificent." <br></p><p>But the atlas does more than be clever and look cool. It's also a window into a world that's now destroyed and forgotten: one in which the <a href="https://earthobservatory.nasa.gov/images/86176/the-north-sea-abloom" target="_blank">North Sea</a> – the body of water between the British east coast and the European mainland – teemed with life. Published in 1883, the atlas devotes one map each to 40-odd species of fish and crustaceans, describing their habits and habitats, and how and when to catch them. Less than a century and a half later, all are now greatly reduced, and some are functionally extinct in the North Sea. </p>
Shifting baselines<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yMzE1OTM3My9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTYxMDAwMDc4MH0.H-B14UvMLU8dlKrZUN2DaqQSlJsFuXdRBLsQX7fvxyU/img.jpg?width=980" id="149a8" class="rm-shortcode" data-rm-shortcode-id="6bc4326d87080399ccae41952ad7c29b" data-rm-shortcode-name="rebelmouse-image" alt="\u200bEach map legend details when the species spawns, when and how they can be caught, what they eat, how much they weight, and what their qualities are. Anchovy, for example, is "excellent for sauce"." />
Each map legend details when the species spawns, when and how they can be caught, what they eat, how much they weigh, and what their qualities are. Anchovy, for example, is "excellent for sauce".
Image: Wellcome Collection. Public domain.<p>We think of our environment as 'normal', but that's because we don't know any better – by definition, we weren't around to experience the 'normal' from before we were born. This phenomenon is called <em>Shifting Baseline Syndrome</em>, and it's no coincidence that this psychological term has <a href="https://oceana.org/blog/daniel-pauly-and-george-monbiot-conversation-about-shifting-baselines-syndrome" target="_blank">found wide currency in fishery science</a>. Because only SBS and the 'generational blindness' it implies can explain how the virtual extinction of global fish stocks over the past century took place with such little notice.</p><p>Consider for a moment the North Sea's waters – grey and soupy today, as everyone thinks they've always been. But thronging its seabeds were once so many oysters, each of which <a href="https://onetrack.club/blogs/news/bringing-back-ocean-biodiversity-with-the-solent-oyster-restoration-project" target="_blank">can filter up to 200 litres of water</a> each day, that the sea must have been a lot clearer, as well as healthier for other marine species.</p><p>The North Sea's native European oysters (<em>Ostrea edulis</em>) have been a prized delicacy for millennia. They were shipped in quantity all the way to Rome, and tasty enough to be mentioned by Pliny the Elder and Juvenal. In more recent centuries, they were the street food of the urban poor. Back in the 1850s, half a billion oysters were sold each year at Billingsgate fish market in London, harvested from the oyster beds that ringed Britain and Ireland. <br></p>
Loss of biodiversity<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yMzE1OTM3NC9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTYzNzE0OTY5OX0.9yWhhNi6Ecofzmpl2AVKj5jAyH8jBxy72oMuNUIkb3E/img.jpg?width=980" id="93a3a" class="rm-shortcode" data-rm-shortcode-id="525458bddf78572c78010bf3c54826a1" data-rm-shortcode-name="rebelmouse-image" alt="\u201cThe conger is very voracious, will attack man in the water, is very prolific, and its youg furnish a great amount of food for other fish. It is also used for isinglass.\u201d" />
"The conger is very voracious, will attack man in the water, is very prolific, and its young furnish a great amount of food for other fish. It is also used for isinglass (a gelatin obtained from fish, used in making jellies, glue, etc. and for fining real ale - Ed)."
Image: Wellcome Collection. Public domain.<p>In particular, Olsen's atlas shows one giant oyster area bigger than Wales, hemmed in by the Dogger bank and the northern coast of the Netherlands. That patch is now gone. As it turned out, Olsen composed his atlas jut before industrial fishing would start to decimate the marine species of the North Sea.</p><p>By the end of the 19th century, the oyster catch started to dwindle, due to overfishing and pollution. By the 1970s, the Pacific rock oyster had to be introduced into the North Sea to satisfy demand. By the 1980s, the European oyster had all but vanished. Heroic efforts are being made to <a href="https://www.ft.com/content/e08e8f16-ea29-11e9-85f4-d00e5018f061" target="_blank">bring back the native oyster</a>, but current stocks are barely 5% of what they were 200 years ago.<br></p><p>Compounding the loss of the oysters themselves is the loss of the reefs they build: these help regulate marine ecosystems, build a habitat for biodiversity – by providing food, nursery grounds and refuge for many fish species. Many of those reefs were destroyed by industrial trawling, which has proved equally devastating for other marine species in the North Sea. </p>
94% decline<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yMzE1OTM3NS9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTYxODkwOTI5Mn0.9N2Rdw9HsZqI0wOsc9LPcMKusK9Qa0VhsOhkRIEjbVY/img.jpg?width=980" id="5a1ce" class="rm-shortcode" data-rm-shortcode-id="cbe3b19f0e9b1bae6e6d88a268fd8206" data-rm-shortcode-name="rebelmouse-image" alt="\u200bThe mackerel was thinly spread across the North Sea, and more numerous to the west, in the Irish Sea and in the Bristol and English Channels." />
The mackerel was thinly spread across the North Sea, and more numerous to the west, in the Irish Sea and in the Bristol and English Channels.
Image: Wellcome Collection. Public domain.<p>Between 1889 and 2007, a <a href="https://www.nature.com/articles/ncomms1013" target="_blank">statistical study of historical fish catch data</a> shows, fish landings from bottom trawl catches in England and Wales declined by a jaw-dropping 94%. In other words: the modern fish stock in the North Sea is just one-seventeenth the size it was in the late Victorian era. That implies "an extraordinary decline in (…) fish and a profound reorganization of seabed ecosystems", the study says. No prizes if you guess what caused the decline: more than a century of industrialised trawling.</p><p>This figure applies to so-called 'demersal' (or bottom-dwelling) species like cod, plaice, haddock and halibut. In particular, haddock had fallen to less than 1% of its former volume, halibut to one-fifth of 1%. Another study suggests that the current biomass of large fish in the North Sea is up to 99.2% lower than if no fishing had occurred. <br></p><p><a href="https://www.youtube.com/watch?v=BnmGbDN278Y" target="_blank">Bottom-trawling</a> is the main method of catching bottom-living fish today. First attested in the 14th century, the process was industrialised from the late 19th century, first with the advent steam trawlers, and greatly expanded in the 20th century. Already in 1885, the UK government examined claims that industrialised fishing depleted stocks and damaged habitats. But conservation efforts came to nothing, among others by the absence of hard data. </p>
Common Fisheries Policy<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yMzE1OTM3OC9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTY0OTIyMTUwNn0.KkkS0oI13wfLSSE45FW-OABBx0Mwth9c3E0v_fUo_hA/img.jpg?width=980" id="7e01e" class="rm-shortcode" data-rm-shortcode-id="b85473e1dc68bc4e44081b9a1634d15e" data-rm-shortcode-name="rebelmouse-image" alt="\u200bShrimp fishing grounds all hug the coast - but are largely absent from the Norwegian and Danish coasts." />
Shrimp fishing grounds all hug the coast - but are largely absent from the Norwegian and Danish coasts.
Image: Wellcome Collection. Public domain.<p>In fact, the increasingly effective methods of industrial fishing have masked the negative effects they have had on fish stocks. According to the study cited above, the recent history of fishery in England and Wales can be divided into four phases:</p><ul><li>From 1889 to the onset of WWI: the fishery fleet is converted from sail to steam. Fishing is rapidly industrialised and intensified. Stocks start to decline, but this is compensated by massive expansion of the catch areas.</li><li>The interbellum (1919-1939): In a second wave of expansion, fishing vessels go as far away as the Arctic and West Africa, managing to increase catches until the late 1950s.</li><li>From the end of WWII to the early 1980s: fast-declining fish stocks in the North Sea and beyond. As a protective measure, Iceland and other countries declare Exclusive Economic Zones of 50, then 200 miles.</li><li>From 1983: the UK (and Ireland) join the European Economic Community, and must adhere to the <a href="https://ec.europa.eu/fisheries/cfp_en" target="_blank">Common Fisheries Policy</a>.</li></ul><p>The CFP is a compromise, forcing EU member states to adhere to fish quotas in order to allow the stocks to recover from overfishing. However, it is estimated that quotas have always been up to 35% higher than the levels advised by scientists as sustainable. In order to minimise displeasure of the fishing industry, the CFP has prioritised maintaining catch levels over maintaining stock levels. <br></p>
Fighting over a comb<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yMzE1OTM4OS9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTYxMzY2MDM3Nn0.6bdUKCerxaFtiGJ_1LUf6IjijchMG5Hbwmlz5mteRIg/img.jpg?width=980" id="da47c" class="rm-shortcode" data-rm-shortcode-id="6b687bada474d9da86a6d1a7f1ad9c21" data-rm-shortcode-name="rebelmouse-image" alt="\u200b"Very wholesome, nutritious and savoury," the herring is "as pleasing to the eye as the taste is grateful to the palate. It is also food for all fish."" />
"Very wholesome, nutritious and savoury," the herring is "as pleasing to the eye as the taste is grateful to the palate. It is also food for all fish."
Image: Wellcome Collection. Public domain.<p>As a result, it is estimated that stocks of demersal fish in the North Sea have declined by 42% since the early 1980s. "In many cases, today's fisheries are sustained by populations of species that should be considered commercially extinct," says the study. The end of the line has been a long time coming:</p><ul><li>In 1889, Britain's sail-powered fishing fleet landed twice as many fish as today's highly sophisticated vessels.</li><li>In 1910, British fishermen landed four times as many fish as they do today.</li><li>The peak year for North Sea fishing was 1938, when 5.4 times more fish were landed in the UK than today.</li><li>Mackerel fishing ceased in the 1970s due to overfishing. The same could soon happen for herring, cod and plaice. </li></ul><p>For the Leave campaign in Britain's 2016 Brexit referendum, the British fishing industry and its perceived suffering at the hands of EU bureaucracy was a major issue. Brexit meant 'taking back control' of British waters and the fish that swim in them, doing away with the limiting quotas imposed by Brussels. </p><p>But the baseline has shifted; the piscatorial richness that informed Olsen's atlas and which once filled the North Sea has gone. And duelling with the European Union over those dwindling fish stocks feels a bit like <a href="https://en.wikiquote.org/wiki/Falklands_War" target="_blank">what Borges said</a> about the absurdity of the Falklands War: "a fight between two bald men over a comb."<br></p>
Beautiful? Yes. Air purifiers? Not so fast.
- A new meta-analysis at Drexel University shows that house plants are not effective for purifying the air of toxins.
- A 1989 NASA report that claimed indoor plants are purifying was not conducted in realistic living conditions.
- Indoor plants have positive effects on our mental health, just not in regards to air quality.
Jill Valley-Orlando organizes houseplants from a recent shipment in the greenhouse at Broadway Gardens on Wednesday, January 16, 2019.
Staff photo by Brianna Soukup/Portland Portland Press Herald via Getty Images<p>This matters as humans spend, on average, 90 percent of their time indoors. On top of this, Cummings and Waring note that, "Much, though not all, of indoor pollution is sourced directly from the indoor environment itself." Air fresheners, paints, glues, printers, and permanent markers (among other manufactured products) add VOCs into the air we breathe. Poor indoor air quality has been implicated in a variety of health risks, including respiratory diseases and headaches.</p><p>All is not lost, however. As the authors note, "Indoor plants, by helping to create a more biophilic indoor environment, may have a positive impact on occupant well-being." However, they write that indoor plants have a tendency to raise humidity levels. Some even produce VOCs of their own.</p><p>Nothing is ever a clear-cut as it seems. This is not a call for removing house plants. They make a lovely addition to home and office environments. We just have to recognize that their appeal is aesthetic and emotional, not as agents in our long quest for purity. </p><p>--</p><p><em>Stay in touch with Derek on <a href="http://www.twitter.com/derekberes" target="_blank">Twitter</a> and <a href="https://www.facebook.com/DerekBeresdotcom" target="_blank">Facebook</a>. His next book is </em>Hero's Dose: The Case For Psychedelics in Ritual and Therapy.</p>
Australia's beloved and bizarre egg-laying mammal could start vanishing in coming years if current trends continue.
- Platypuses are nocturnal, semiaquatic animals that are endemic to Australia and Tasmania.
- A new study suggests that the species could lose half its population over the next 50 years, due mainly to drought, human development and climate change.
- In 2019, the United Nations reported that some 1 million species of plants and animals are at risk of extinction.
Pixabay<p>"There is an urgent need for a national risk assessment for the platypus to assess its conservation status, evaluate risks and impacts, and prioritize management in order to minimize any risk of extinction," Bino <a href="https://www.sciencedaily.com/releases/2020/01/200121112922.htm" target="_blank">told</a> <em>Science Daily.</em></p><p>The study estimated the future decline of platypus populations by considering current rates of climate change, drought, and land and water development. Under this model, the results showed that the platypus population is likely to drop 47 percent over the next 50 years. Drought is expected to be a particularly deadly threat to the species.</p>
Heinrich Harder/Public Domain<p>Australia has recently suffered some of its worst droughts on record. The researchers suggested that even more extreme droughts are likely to occur in the future, considering that the changing climate will bring even hotter temperatures. Droughts can destroy platypuses' burrows, which the animal usually constructs by digging into the riverbank with its claws. When droughts dry up these hiding spots, platypuses are forced to move into new areas where they risk becoming prey to predators like foxes, dogs, and cats.</p><p>Droughts can also increase the likelihood of deadly bushfires. The <a href="https://bigthink.com/strange-maps/australia-bushfires-photo">current bushfire crisis</a> in Australia wasn't mentioned in the recent study, but experts estimate that some 1 billion animals have been killed so far in the fires. As for how many platypuses died:</p><p>"The short answer is that we simply don't know," Josh Griffiths, an ecologist with the environmental consulting firm Cesar Australia, <a href="https://www.atlasobscura.com/articles/australia-platypus-bushfire" target="_blank">told</a> <em>Atlas Obscura</em> in an article published January 24, 2020. "The scale of the fire we've got at the moment is unprecedented. [...] It's one more nail in their coffin."</p>
How to save the platypus<p>Human development, especially that which involves altering rivers, is another major threat to the platypus. Study co-author Richard Kingsford, director of the UNSW Centre for Ecosystem Science, noted that many platypuses live in areas of Australia currently undergoing development.</p><p style="margin-left: 20px;">"These include dams that stop their movements, agriculture which can destroy their burrows, fishing gear and yabby traps which can drown them and invasive foxes which can kill them," Kingsford told<em> Science Daily</em>.</p><p>The researchers offered several suggestions for how to protect the platypus:</p><ul><li>Ban enclosed cray-fish traps</li><li>Prevent land clearing in key areas</li><li>Build "platypus-ways" that provide safe passage from ferals predators</li><li>Citizens can report platypus sightings via the app <a href="http://platypusspot.org/" target="_blank">platypusSpot</a></li></ul>
The relatively quick evolution of nine unusual shark species has scientists intrigued.
- Living off Australia and New Guinea are at least nine species of walking sharks.
- Using fins as legs, they prowl coral reefs at low tide.
- The sharks are small, don't be frightened.