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Heaviest-Black-Hole-in-the-Universe-Revealed-2

Messier 87 (M87) Galaxy

Messier 87 is a strange and extraordinary galaxy.  For one thing it was discovered and named in 1781…even though the nature of galaxies (and the fact that there are more than one such “island universes” was not understood until 1923).  Messier 87 was discovered by the great Charles Messier who was cataloging weird celestial blobs that could confuse comet hunters.   The galaxy lies near the center of the Virgo supercluster of which our own lovely (albeit provincial) galaxy, the Milky Way, is a part. Formed by the merger of multiple galaxies, M87 is huge and contains more than a trillion stars–4 times the number of stars in the Milky Way.  Additionally M87 is surrounded by more than 12,000 globular clusters (the Milky Way has perhaps 200 of these miniature satellite galaxies).  Whereas the spiral Milky Way is “blue and new” with ample quantities of hydrogen to form new stars, the globular Messier 87 is “red and dead”: new star formation has slowed and the great elipsoid mass of stars is slowly dying (insomuch as galaxies can be said to live to begin with).  The stars visible now are mostly middle aged main sequence stars or tiny long-lived red dwarves (tiny for stars…still not something you could pick up and put in your hatchback).

Adapiforme_fossil.

47 million year old Adapidae fossil from Germany

Messier87 is approximately 53 million light years away.  The light that we can observe from it today originated during the Eocene, when the first little primates evolved on Earth and those photons have been streaking toward us through the great emptiness at 300,000 kilometers per second since when our direct ancestors were anxious lemur-squirrel guys staring pensively up at the stars.

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A artist’s conception of such a black hole

The center of this monstrous astronomical entity is a  supermassive black hole 6.5 billion times the mass of the sun (for reference, the sun is 333,000 times the mass of Earth–so this black hole has the mass of 2,164,500,000,000,000 Earths). A horrifying & beautiful relativistic jet of ionised matter 1.5 kiloparsecs (5000 light years) long is emerging from the black hole.

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Why do I bring this up?  Because we photographed the black hole!  This is the first time we have accomplished such a feat.  You can read about the esoteric details of how astronomers achieved such a thing by clicking on today’s Google Doodle (so I guess today’s blog post will not be a completely original/unique subject),  I suspect you have seen the picture already. Yet even the eye-of-Sauron glory of this image (which was taken by a pan-global network of radio telescopes) does not exactly capture the scale of the black hole.  My imagination is equiped for may things, but is not really much good for processing numbers bigger than a few thousand.  The diameter of this black hole is roughly approximate to the orbit of Uranus and it has the mass of a small galaxy.  So I guess keep that in mind when looking at the little orange eye. Now I am going to go lie down and hold my pet cat.

Pity the flounder! Pity, I beg thee...

Pity the flounder! Pity, I beg thee…

Adolescence is difficult. Puberty is an awkward transitional time when the winsome cuteness of childhood departs forever but is not fully replaced by the graceful strength and confidence of adulthood. But before you have a PTS flashback to those rough years, spare a moment of pity for the poor flounder. Flounders (and other flatfish like halibuts, soles, and flattest of them all, turbots) are born…err hatched like us with two eyes on either side of their skull. As tiny transparent larvae living among the zooplankton, flounder fry can see a panoramic view of the ocean so as to better evade predators. As they dart through three dimensions, their bilateral symmetry is like that of the rest of the vertebrates.

As searingly depicted in this stunning diagram

As searingly depicted in this stunning diagram

Then, as they grow into adult fish, a strange and remarkable metamorphosis occurs. Bones in the flounder’s skull distort and one eye migrates across its head so that both eyes are on one side of its face. Imagine if your left eye traveled over the bridge of your nose to permanently join your right eye on the right side of your face!

An adolescent flatfish--the eyes are just beginning to creep to one side (photo for PBS Nova)

An adolescent flatfish–the eyes are just beginning to creep to one side (photo for PBS Nova)

Of course eye migration is but one aspect of the flounder’s change to adulthood. The fish begin to swim at an angle. One side of their body becomes flecked with color while the other becomes white (the better to merge into the two dimensional world of the bottom). Speaking of color, the once transparent fry becomes opaque! Their mouth opens on one side of their head and they must learn to swim like a flying carpet.

flounder
But don’t let their remarkable transition and their comic appearance deceive you. The flatfish are extraordinary predators and they are also geniuses at avoiding the many toothy hunters of the ocean. Their close set eyes protrude above the sand and see unwary prey with acuity and laser focus. Fossil finds from Monte Bolca, a beautifully preserved Eocene coral reef, show that the flatfish were evolving into their current form 45 million years ago (as the primates were taking to the trees, the bats were first taking wing, and the little dawn horses were scampering through the endless tropical groves). For at least 45 million years the flatfish (which, I should have mentioned, constitute the order Pleuronectiformes) have been camouflaged at the bottom of the sea feasting on shrimp and minnows while the world blinked and didn’t notice them. They are still out there thriving, even as whole parts of the ocean ecosystem collapse. It is a striking reminder that wrenching changes can work out for the best!

An adult Turbot

An adult Turbot

Different fossil plants and animals from the lacustrine deposits of the McAbee Flora of the Eocene (British Columbia, Canada)

Different fossil plants and animals from the lacustrine deposits of the McAbee Flora of the Eocene (British Columbia, Canada)

Today we return to the long-vanished summer world of the Eocene (the third epoch of the Cenezoic era). During most of the Eocene, there was no polar ice on Earth: a balmy temperate summer held sway from Antarctica to Svalbard. British Colombia was covered by a tropical rainforest where palm trees and cycads contended with warm weather conifers (and with the ancestors of elms, cherries, maples, and alders). Within this warm diverse forest, which thrived between 55 and 50 million years ago, lived numerous strange magnificent birds and insects. Shoals of tropical fish thronged in the acidic foaming waters (which were practically carbonated—since the atmospheric carbon dioxide levels of the Eocene were probably double that of the present).   The mammals of this lovely bygone forest were equally splendid–strange proto-carnivores not closely related to today’s mammalian predators,  weird lemur analogs, and strange ur-rodents. This week the discovery of two new mammal species was announced.  These remarkable fossil finds provide us with an even better picture of the time and place.

a reconstruction of the early Eocene  in northern British Columbia, a tapir-like creature from the genus heptodon with a while tiny proto-hedgehog in the foreground. (Julius T. Csotonyi)

a reconstruction of the early Eocene in northern British Columbia: a tapir-like creature (genus Heptodon) with a tiny proto-hedgehog in the foreground. (Julius T. Csotonyi)

One of the two creatures discovered was a tapir-like perissodactyl from the genus Heptodon. The newly discover tapir was probably about the size of a large terrier. I really like tapirs (and their close relatives) but these remains are not a huge surprise–since many perissodactyls thrived in North America during the Eocene. The other fossil which paleontologists found is a surprise—an adorable surprise! Within a stone within a coal seam was a tiny jaw the size of a fingernail. Such a fossil would have been all but impossible to study in the past, but the paleontological team led by David Greenwood, sent the little fossil to be scanned by a CT scanner and then imaged with a 3D scanner. The tiny jaw was from a diminutive hedgehog relative since named Silvacola acares.  The little hedgehog grew to a maximum adult size of about 6 cm (2.3 inches) long or approximately thumb-sized. Since it probably lacked spines, this miniature hedgehog was a bit different than the modern hedgehog, but it was definitely a relative.

As discussed in previous posts, I like to imagine the balmy Eocene, when so many mammals which are now the mainstay of our familiar Holocene/Anthropocene world got their first start. It makes it even better to imagine that the thickets were filled with endearing hedgehogs the size of bumble bees.

Rodhocetus (by Pavel Riha)

Rodhocetus (by Pavel Riha)

This endearing beasty is Rodhocetus, a long extinct proto-whale which lived during the mid-Eocene (approximately 40 to 50 million years ago). Rhodhocetus fossils are found in contemporary Pakistan, but the world has changed greatly since the warm Eocene: the creatures did not live on the tops of mountains, but rather in estuaries and shallow seas.

Rodhocetus

Rodhocetus

The early cetaceans shared ancestors with the artiodactyls (cows, pigs, hippos, goats, and suchlike even-toed ungulates) and indeed the first cetaceans, from the beginning of the Eocene, look somewhat like weird squashed hippos or water cows. By the middle of the epoch, however the familial similarities were beginning to fade.

06-14-P-02-G-01-KlausmeyerRodhocetus-full_1

Rodhocetus specimens have elongated hands and feet–which were almost certainly webbed. Their hipbones were not fused to their backbones, which gave them additional speed and maneuverability in the water, where they hunted for fish and squids. Although the creatures were adapted for an aquatic predatory lifestyle, they could still drag themselves up on land, unlike their descendents the modern whales and dolphins. Additionally they still retained fur, and double-pulley heelbones (the latter of which convinced paleontologists that whales and cows are relatives who share an ancestor).

An artist's conception of Poebrotherium (an early camel)

An artist’s conception of Poebrotherium (an early camel)

Camelids are believed to have originated in North America.  From there they spread down into South America (after a land bridge connected the continents) where they are represented by llamas, alpacas, vicuñas, and guanacos.  Ancient camels also left North America via land bridge to Asia. The dromedary and Bactrian camels are descended from the creatures which wandered into Beringia and then into the great arid plains of Asia.  Yet in their native North America, the camelids have all died out.  This strikes me as a great pity because North America’s camels were amazing and diverse!

An illustration of the size of Gigantocamelus

An illustration of the size of Gigantocamelus

At least seven genera of camels are known to have flourished across the continent in the era between Eocene and the early Holocene (a  40 million year history).  The abstract of Jessica Harrison’s excitingly titled “Giant Camels from the Cenozoic of North America” gives a rough overview of these huge extinct beasts:

Aepycamelus was the first camel to achieve giant size and is the only one not in the subfamily Camelinae.  Blancocamelus and Camelops are in the tribe Lamini, and the remaining giant camels Megatylopus, Titanotylopus, Megacamelus, Gigantocamelus, and Camelus are in the tribe Camelini.

That’s a lot of camels–and some of them were pretty crazy (and it only counts the large ones—many smaller genera proliferated across different habitats).  Gigantocamelus (as one might imagine) was a behemoth weighing as much as 2,485.6 kg (5,500 lb).  Aepycamelus had an elongated neck like that of a giraffe and the top of its head was 3 metres (9.8 ft) from the ground.  Earlier, in the Eocene, tiny delicate camels the size of rabbits lived alongside the graceful little dawn horses.  This bestiary of exotic camels received a new addition this week when paleontologists working on Ellesmere Island (in Canada’s northernmost territory, Nunavut) discovered the remains of a giant arctic camel that lived 3.5 million years ago. Based on the mummified femurs which were unearthed at the dig, the polar camel was about 30 percent larger than today’s camels.   The arctic region of 3.5 million years ago was a different habitat from the icy lichen-strewn wasteland of today.  The newly discovered camels probably lived in boreal forests (rather in the manner of contemporary moose) where they were surrounded by ancient horses, deer, bears and even arctic frogs!  Testing of collagen in the remains has revealed that the camels are closely related to the Arabian camels of today, so these arctic camels (or camels like them) were among the invaders who left the Americas for Asia.

Aepycamelus (painting by Heinrich Harder)

Aepycamelus (painting by Heinrich Harder)

The bones are a reminder of how different the fauna used to be in North America.  When you look out over the empty, empty great plains, remember they are not as they should be.  All sorts of camels should be running around.  Unfortunately the ones that did not leave for Asia and South America were all killed by the grinding ice ages, the fell hand of man, or by unknown factors.

An artistic reconstruction of the newly discovered Arctic camels

An artistic reconstruction of the newly discovered Arctic camels

Agriculture is almost unknown in the natural world. Human beings are the only vertebrates known to grow crops or keep livestock (with the possible exception of damselfish which carefully tend little algae gardens).  And yet we were not the first animals to invent the concept.  Ants have farmed fungi within their tunnels for tens of millions of years.  Ants also keep aphids in captivity in order to “milk” them of sugary secretions–or to eat them outright.  It is possible that beetles, termite, or snails came up with the concept first, but most evidence points to ants as the first farmers.

An Ant Milking Aphids

Ants do not have a shabby operation either. Leaf cutter ants form the largest and most complicated animal societies known on Earth (other than our own) and a single colony can have over 8 million individuals.  Leaf cutters are an ideal example of how adept ants are at farming fungi.  Four different castes of worker ants work together to bring back leaf fragments and integrate them into huge fungal gardens. Different species of leafcutters cultivate different fungi from the Lepiotaceae family.  Certain bacteria with antifungicidal and antibacterial properties grow within the metapleural glands of the ants.  The worker ants use these bacteria to “prune and weed” dangerous or unproductive organisms out of their gardens.  Older (more expendable) worker ants carry waste products from the hive to a waste pile where they stir the hive wastes together to aid in decomposition.  The waste-management job brings the danger of fungal or bacterial contamination and contaminated ants are exiled to certain death in order to keep the gardens safe.  Additionally dead ants from within the hive are carefully placed around the waste pile so as to protect the hive from their decomposition.

Leaf Cutter Ants at the Cameron Currie Lab arrange cut-up leaves into their fungal garden.

According to geneticists who study the rates of mutation within the various fungal cultivars, ants began their farm relationship with fungi around 50 million years ago in the warm Eocene epoch (an era which saw many of the critical relationships in modern ecosystems begin).

 

Digital Cut-away of an underground leaf-cutter nest

Scientists are also beginning to understand the means by which ants herd their little flocks of aphids.  The aphids are smaller insects which feed on the saps and juices of plants (which they suck out by means of specialized mouthparts called stylets).  The ants prevent the aphids by flying away by tearing off their wings.  The feet of the ants produce chemicals which tranquilize and subdue the aphids and keep them from escaping the “pastures” near the ant colonies.  It is believed that aphids also derive certain benefits from this arrangement since the aggressive ants protect them from many of their natural predators.

An Ant with a “herd” of Aphids

For years naysayers belittled the farming achievements of ants suggesting they were little more than symbiotic arrangements.  However as entomologists study the ants more carefully they increasingly discover just how complicated and sophisticated those relationships are (involving as they do numerous symbiotic relationships with bacteria in order to produce the chemicals necessary for agricultural control).  Additionally, what are humankind’s relationships with our crops and animals if not huge harrowing examples of symbiosis?

A human (black), an African Elephant (gray), a Mastodon (french blue) and a Paraceratherium (sky blue)

The largest land animal alive today is the mighty African elephant, however even the largest adult bull elephants were dwarfed by the largest land mammal ever to exist.  The giant herbivore Paraceratherium stood 5.5 metres (18 ft) tall at the shoulder.  When standing upright the creature’s head (which was approximately the same size as character actor Danny Devito) was about 8 metres (26 ft) above the ground.  Although debate continues about how much the beast weighed, reasonable estimates suggest it could have massed from 15 to 20 metric tons which means that the animals were as large as mid-sized sauropod dinosaurs from the previous era.  Partial skeletons of Paraceratherium were discovered by different scientists at different times–which has confusingly resulted in three different names for the genus: 1) Paraceratherium  which means”near horn animal” in Greek; 2) Indricotherium which was derived from a mythical Russian progenitor-monster called the Indrik-Beast; and 3) Baluchitherium which means “Baluchistan beast”, in honor of Baluchistan, an arid portion of the Iranian plateau, where a fossil specimen was unearthed.  Paleontologists prefer to call the genus “Paraceratherium,” however, thanks to TV specials and museum shows the name “Indricotherium” remains popular with the public.

Artist’s Conception of Paraceratheriums Migrating (from asecic.org)

Paraceratheriums were perissodactyls.  The giant creatures were most closely related to the living rhinoceroses (although they shared ancestors with tapirs and horses as well).  Paraceratherium’s immense size allowed it to eat the branches and leaves of large trees.  They ranged across what is now Central Asia across Iran, India, Pakistan, Mongolia, Kazakhstan, and China.  The various species of Paraceratherium had long graceful necks somewhat like that of Okapis.  Additionally they possessed nimble elongated upper lips with which to strip leaves off of branches.  These lips were no quite trunks but probably resembled the long grasping snout/lips of tapirs.  Although Paraceratherium was closely related to rhinoceroses, they lacked the rhino’s characteristic horns—their giant size meant they did not need them.  The genus originated in the Eocene and flourished during the Oligocene—a golden age of perissodatyls.  However as the global cooling became more pronounced in the late Oligocene, the great creatures gradually vanished.

Fossil Paraceratherium skeleton in a museum

Antarctica Seen from Space

Imagine standing high above planet Earth and looking down at the blue and white band of seas surrounding Antarctica.  You are looking at one of the most important features of the Earth’s surface.  The turning of the planet and strong westerly winds drive the cold deep waters of the Southern Ocean into the planet’s largest and most powerful current system, the Antarctic Circumpolar Current (ACC).  The clockwise current isolates the frozen continent into its own self-replicating climate. Since there are no great land masses lying in the ring of open water at these latitudes, the ACC also forces waters from the ocean depths up to the surface.  This upwelling brings rich nutrients from the depths and causes immense blooms of phytoplankton (which in turn nurture life throughout all the world-ocean).  Additionally the current stirs the circulation of the Atlantic, Pacific, and Indian Oceans.

The ACC has been known to sailors for centuries.  A sailing ship can travel west along the current with great speed (if the sailors have the bravery and stamina to confront the fierce winds of “the roaring forties”).   The “clipper route” was the fastest sailing route around the world, but it was dangerous.  The three great capes (Cape Horn, the Cape of Good Hope, and Cape Leeuwin) all claimed innumerable lives as did wind, ice, and storm.  Today the clipper route has been abandoned as self-powered ships bring their cargoes of plastic junk straight across the ocean from China (and then cut across the Panama Canal) but sailing enthusiasts still recognize the fastest way to ride the wind around the planet.  The major circumnavigation sailboat races all travel the clipper route.

“Roaring Forties” (Gordon Frickers, oil on canvas)

The true history and significance of the ACC vastly exceeds the paltry recent concerns of navigation and world trade.  Geologists estimate that the ACC current began spinning around 34 million years ago at the end of the Eocene epoch as Antarctica split from Australia and drifted further south.  Back when Antarctica and Australia were still connected, the great amalgamated continent was a place where cold southern water and chill weather mixed together with tropical warmth—thus causing the whole planet to warm up.  However when Antarctica broke away and drifted south, it started a series of climate feedback loops.  The oceans around the continent began to freeze and ice started to build up on the mountains.  An entire continental ecosystem began to change in the cold.  The tropical forests (which had been filled with strange marsupials) began to die and become tundra.  As the Oligocene progressed and Drake’s Passage widened, the rivers–once filled with catfish–turned to ice.  The landmasses of Antarctica became crushed down under immense glaciers.  Antarctica died in the cold.  By 15 million years ago it became as it is now–home to only tardigrades, lichen, and a handful of visiting birds and seals.

The Transantarctic Mountains (photo by John Goodge)

Even now the Antarctic Circumpolar Current still isolates the continent from the warmth of the rest of the world.  Yet through upwelling of iron and other nutrients, the current bolsters an immense fecundity of phytoplankton–the great primary producer of the ocean.  Masses of copepods and krill feed on the algae and the diatoms and they in turn are eaten by fish, mollusks, mammals, birds, filter feeders…everything.  The great southern oceans are among the most diverse and strange habitats for living things.  It is there that the largest mollusk on the planet is found—which is the subject of an upcoming post.

Model of a Moeritherium

Our story takes us back 37 million years ago to the hot moist swamps of the Eocene (again).  In the swamps of Africa lived a long low wallowing mammal 3 meters (9.8 feet long) and 70 centimeters (2.25 feet) tall.  This swamp dweller occupied the same sort of niche now taken by pygmy hippos and capybaras—it was an amphibious grazer which lived on soft water plants and could slip into the water to avoid land predators (and vice versa).  The animal was named Moeritherium, a genus consisting of several similar species, all now long extinct.

Moeritheriums (painting by Heinrich Harder)

Moeritheriums mostly had peg like teeth for grinding up vegetation, but the creatures’ second incisor teeth were elongated like daggers for display, defence, and rooting. So Moeritherium was really another saber toothed creature (like walrus, Smilodon, and Odobenocetops), but we never think of their closest living relatives as saber-toothed so it is hard for me to think of them that way.  In fact Moeritherium’s closest relatives overshadow all the details about the low-slung swamp-dwelling creature entirely because they are one of the most magnificent and intelligent orders of creature on planet Earth.  The Moeritheriums wallowing in the African swamps long ago were among the very first Proboscideans–an order of mammals including elephants, mammoths, mastodons, and gomphotheres.

An artist’s conception of a Moeritherium

Moeritheriums probably did not have a long trunk like today’s elephants, but they did have a long flexible upper lip like tapirs.  Their eyes and ears were high up on their head so they could submerge themselves but still watch the surrounding landscape. They were not direct ancestors of the elephants and mammoths but instead descended from a common ancestor, Eritherium, a rabbit sized progenitor, which was rather like a hyrax.  Moeritheriums were highly successful in their day, but they disappeared as the Eocene climate dyed up and cooled down.  Fortunately several other families of proboscideans like the paleomastodons and the Phiomias were there to carry on the magnificent order of Proboscideans.

Paleomastodon (painting by Heinrich Harder)

Wadi Al-Hitan, Egypt

In the desolate desert 150 kilometers southwest of Cairo there is a fearsome arid valley (wadi) of cliffs, carved buttes, and sandblasted erratic boulders.  The bleached landscape has an otherworldly emptiness as though it were located on a lifeless alien planet, though if you look closely, the desert is filled with austere furtive life like dorcas gazelles, tiny sand colored lizards, cobras, scorpions, and fennec foxes. The name of the place is even more otherworldly—“Wadi Al-Hitan” which is Arabic for “valley of the whales” and although the great smooth rocks buckling out of the sand might momentarily be taken for the backs of huge whales, the utter absence of the ocean (or of water of any kind) makes the name seem fanciful. The nearby Mount Garet Gohannam (which means mountain of hell because of the way it glows like flames at sunset) seems to be more aptly named.

Whale fossil at Wadi Al-Hitan

However the name of Wadi Al-Hitan is remarkably literal–for the valley contains the remains of hundreds of huge ancient cetaceans which died in the Eocene and were fossilized in the yellowish sandstone.  Forty million years ago the valley was a marine lagoon.  Although the remains of numerous sirenians, sawfish, sharks, rays, sea turtles, marine crocodiles, sea snakes, and even swamp dwelling moeritheriums have been discovered in the wadi, the valley takes its name from the most spectacular and numerous fossils which belong to four different species of primitive whales.  The most commonly discovered fossils belong to Dorudon, which was 3-5 meters long (9-15 feet) and fed on fish and mollusks, and to Basilosaurus, which was 15-22 meter (50-72 foot) and fed on everything else in the ocean.

Basilosaurus was first discovered in Louisiana in the early 19th century.  Its immense size and serpentine form initially convinced naturalists that it was a marine reptile and they misnamed the creature Basilosaurus (which means “king lizard”).  The mistake soon became obvious and Basilosaurus was classified among the Archaeoceti, a paraphyletic suborder of the cetaceans, however the giant kept its dinosaur name.  Different species of Basilosaurus flourished in oceans worldwide during the wet, tropical Eocene and, even though they were obviously very adept at ocean living (indeed rising to the top of the food chain) the creatures betray vestiges of terrestrial living which modern whales have entirely dispensed with. Not only do Basilosaurus fossils have teeth and jaws which retain reatures from their artiodactyl ancestors, they also have tiny vestigial back legs a mere half meter in length (which would scarely help a 22 meter animal get around).  Additionally Basilosaurus was different from modern whales in that it probably moved with eel-like horizontal thrashing of its long tail (modern whales move their flukes vertically).  Basilosaurus probably did not dive very deeply, but moved about near the surface of the oceans hunting for smaller marine animals.

Basilosaurus from “Life in the Ancient Seas Exhibit” at the Smithsonian Institution, National Museum of Natural History

Although Wadi Al-Hitan was discovered by Europeans in 1902-1903, some archaeologists and anthropologists have speculated that it was known long before that and have been irresistibly drawn towards comparing basilosaurus with the giant crocodiles and earth spanning serpent gods which populate ancient Egyptian cosmology.

Detail from painting (Life in the Ancient Seas Exhibit: Smithsonian Institution, National Museum of Natural History)

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