Gigantic Prehistoric Creature Discovered

Quarries offer a glimpse into Earth’s deep past by revealing fossils of creatures that once roamed the Earth. A discovery in a Russian quarry had revealed a colossal carnivore that lived millions of years ago.

A rich fossil site is the Kosyakino quarry near Stavropol, Russia. The quarry was discovered in 1938 and gained recognition for its concentration of ancient vertebrates. Fossils found there include birds, reptiles and amphibians from roughly 5.5 to 6 million years ago. In 1961, the quarry was closed to industrial use to safeguard its paleontological treasures.

A jawbone was among the early findings there. It was initially believed to be from a large hyena-like bear. It remained in storage, labeled with that assumption, for decades. But eventually, the specimen was revisited, which sparked a reevaluation.

Closer inspection revealed that the fossil represented a new type of massive bear, later named Huraca borissiaki. Though incomplete, it displayed a deep, sturdy structure, widely spaced teeth, and massive carnassial teeth. These pointed to an apex predator unlike any other bear at the time.

Huracan borissiaki rivaled the size of the largest bear ever recorded. This means it ranked among the greatest carnivorous bears to have ever lived.

The history of the Huracan genus stretches back approximately 6 million years ago. The earliest fossils were uncovered in China, but they spread widely, reaching North America, East Asia, and Europe (although they disappeared from Europe soon after their arrival).

Stavropol is north of the Caucasus Mountains, a region that bridges Europe and Asia. This location reinforces the idea of a prehistoric migration route of ancient megafauna.

The Miocene lasted from about 23 to 5 million years ago. During it, forests receded, grasslands expanded, and animals adapted to new ways of life.

This reconstructed jaw implies an animal of immense strength. Its teeth could shear through muscle and crack bone, which would indicate a diet of large prey. It was a specialist in survival.

A debate has arisen about where Huracan borissiaki fits in the bear lineage. Its features suggest it was a branch that evolved and vanished before modern bears appeared.

In addition, the quarry’s sediments tell a story. Layers of ash, pollen, and minerals indicate fluctuating climates and ancient rivers, so that Huracan borissiaki lived in a landscape that was constantly changing.

Why this titan disappeared remains unclear. It’s possible that changing climate, new predators, or dwindling prey led to its extinction.

 

https://www.msn.com/en-us/news/other/gigantic-prehistoric-creature-discovered-in-russian-quarry-is-a-new-species/ss-AA1OZdep?ocid=hpmsn&cvid=690d5eedff2e4e36a861e6a01db38aae&ei=75#image=19

A New Type of T Rex

A remarkably complete tyrannosaur specimen was unearthed in the middle of Montana. It may finally settle one of the most contentious arguments in paleontology. While it’s at it, it might also upend our understanding of Tyrannosaurus rex, one of the most famous extinct animals on Earth.

The new fossil, along with others that had been assumed to be teenaged T. rex, are actually part of a distinct group called Nanotyrannus. Researchers had discovered differences in the bones, as well as evidence that the new fossil was a mature adult that had stopped growing, not an immature T. rex. The study also creates a more diverse picture of predators of the late Cretaceous by making the case that there were two species of nanotyrannus.

Originally, nanotyrannus were first identified as a separate species in the mid-1940s, but many came to believe they had been misclassified. They said the smaller versions were simply T. rex teenagers.

But if these were not teenagers, other questions arose: Did these different species interact? Did they hunt different prey? What did T. rex adolescence look like?

This paper states that Nanotyrannus is a distinct tyrannosaur species. Which indicates a reassessment of tyrannosaur classification is needed. Which is how science works.

For decades, nanotyrannus proponents had been marginalized by scientific consensus that they were young tyrannosaurs.

In a paper published in 1946, Smithsonian paleontologist Charles Gilmore described a new carnivorous dinosaur whose skull was found in Montana. At the time, he described it as a Gorgosaurus, a slightly smaller species of tyrannosaur. Four decades later, the skull was reanalyzed and a new paper proclaimed it a nanotyrannus.

Nanotyrannus lancensis was less than half the length of T. rex, although it was a relatively long-limbed animal. It is thought it would have been more graceful, not like the stocky, stomping brute of a T. rex.

Thomas Carr suggested in 1999 that nanotyrannus were simply youthful T. rex, and that explanation took hold.

In 2021, a North Carolina Museum acquired a 30,000 pound slug of bone and rock. They thought it contained a juvenile T. rex and a triceratops that had been buried together in Montana. Soon, they realized it was not a juvenile because its hand was really big. Far bigger than the hand of a fully grown T. rex.

A detailed analysis of the fossil found distinctive differences, such as the way cranial nerves threaded through the skull and the patterns of sinuses in the skull. Then, they cut into a limb bones, where the growth rings showed it to be about 20 years old, and it was a mature individual that had stopped growing… at less than half the length of a full-grown T. rex.

So they reexamined 120 existing fossils. One (called Jane) was assumed to be a young T. rex. She was a nanotyrannosaur, but a different species than the others they were studying.

So, kids can still have a favorite dinosaur, even a favorite tyrannosaur. It just might not be the well-known tyrannosaurus rex.

 

https://www.msn.com/en-us/news/world/one-of-science-s-biggest-dinosaur-debates-may-finally-be-settled/ar-AA1PvttY?ocid=hpmsn&cvid=6904de58713a4fa5aca269a56dd9bb74&ei=71

Nine-Foot-Long Millipede

A long, long time ago, millipedes were nine-foot-long. Weighing in at 110-pounds, this creature is called Arthropleura and is the largest arthropod to ever live.

This all happened during the Carboniferous period, roughly 300 million to 360 million years ago. The Earth’s atmosphere at that time was rich with oxygen, making it possible for some animals to swell to monstrous size, such as dragonflies with two-foot wingspans.

However, Arthropleura fossils discovered since the 1800s were often only remnants of headless exoskeletons left behind during molting. A new study states researchers have finally pieced together what the animal’s head was like. The breakthrough came from two well-preserved juvenile Arthropleura fossils found in France. These specimens were less than two inches long, but they provided the first-ever glimpse of Arthropleura’s head.

Apparently, this insect’s head was a rough circle adorned with two antennae, a small mandible hidden underneath, and eyestalks protruding from the sides.

Arthropods, are a group of invertebrates that includes crustaceans, spiders, insects, centipedes and millipedes. There has been fierce controversy about Arthropleura’s position on the arthropod family tree since its discovery in 1854. Was it a millipede or a centipede? Scientists weren’t sure.

During examinations of the new, complete fossils, scientists found that it had the body of a millipede but the head of a centipede. It had two pairs of legs per body segment, where centipedes only have one pair per segment. Its jaw position resembles that of a centipede, but its shape and antennae are most similar to those of a millipede. One feature is not seen in any living members of the millipede or centipede families—eyestalks. The eyestalks resemble a crab’s, which could point to the creature having an amphibious youth before becoming terrestrial in adulthood.

Researchers have also concluded that Arthropleura probably chewed on decaying plants like the millipedes of today, rather than hunting prey like a centipede. Its anatomy indicates that it was not carnivorous. It did not have a centipede’s ‘fangs’ or any appendages built for hunting. In addition, having two pairs of legs per segment affected its locomotion and implies it was rather slow.

After piecing together these bits of evidence, the team says the Arthropleura is most closely related to millipedes.

These ancient millipedes lived between 290 million and 346 million years ago, skittering around the Earth’s tropical equator with other massive arthropods, like two-foot-long scorpions. The leading theory for this gigantism is that the oxygen concentration was estimated at 30% during the Carboniferous era compared to the 21% of today. More oxygen in the air may have let insects grow much bigger.

While finding the juvenile Arthropleura has provided some answers, there are more questions to be answered with future fossil discoveries. Did the Arthropleura use tracheae for breathing, or lungs like spiders? That’s just one question that hasn’t been answered yet.

I find modern insects are frequently creepy, at least, to my mind. I definitely do not want to come across a nine-foot-long millipede.

 

https://www.msn.com/en-us/news/technology/fossils-reveal-the-face-of-an-extinct-nine-foot-long-millipede-the-largest-arthropod-to-ever-live/ar-AA1sJDJt?ocid=hpmsn&cvid=ea032899905c4745973f745a67d92256&ei=129

Colorado 'swamp dweller' mammal

Working near Rangely, Colorado, paleontologists have uncovered an unknown state resident—a fossil mammal about the size of a muskrat that may have scurried through swamps during the Age of Dinosaurs.

They identified the creature from a piece of jawbone and 3 molar teeth, and named it Heleocola piceanus. It lived in Colorado roughly 70 to 75 million years ago, at a time when an inland sea covered large portions of the American West. “Heleocola” roughly translates to “swamp dweller” in Latin.

Said one team member, “Colorado is a great place to find fossils, but mammals from this time period tend to be pretty rare. So it’s really neat to see this slice of time preserved in Colorado.”

Compared to the much larger dinosaurs living at the time, like tyrannosaurs or horned ancestors of Triceratops, this new fossil might seem tiny and insignificant. But it was surprisingly large for mammals at the time.

This discovery helps paint a more complete picture of a Colorado that would be all but unrecognizable to residents today. Seventy million years ago, this area was where land met water. Creatures like turtles, duck-billed dinosaurs and giant crocodiles may have flourished in marshes and estuaries, gorging themselves on wetland vegetation and fish.

The bit of mammal jaw emerged from a slab of sandstone that was collected from the site in 2016. The fossil measured about an inch long.

Before an asteroid killed off the non-avian dinosaurs 66 million years ago, mammals tended to be small—about the size of today’s mice or rats. They are largely identified from the tiny teeth they left behind.

In comparison, this one was positively huge. A cousin to modern-day marsupials, this animal weighed 2 pounds or more. But it’s not quite a record. The Didelphodon, another fossil mammal from the same period, may have weighed as much as 11 pounds. H. piceanus’ teeth indicate it dined on plants, with a few insects or small animals mixed in.

 

https://www.msn.com/en-us/news/technology/paleontologists-discover-colorado-swamp-dweller-mammal-that-lived-alongside-dinosaurs/ar-AA1sNCLe?ocid=hpmsn&cvid=ed46623d933043f19069e3bf9a8f9350&ei=83 

Armored Dinosaur had a Bulletproof Vest

Many dinosaurs relied on plate armor to keep them safe from predators. But one went so far as to grow a ‘bulletproof vest’ over its plate armor. The best-preserved dinosaur fossil on record is a type of ankylosaur called a nodosaur. The nodosaur was a herbivore that grew 18 feet long and lived 110 to 112 million years ago. One of these fossils was so well preserved, scientists were able to determine the strength of its keratin plates and the bony spikes that covered them. It is estimated that the nodosaur could survive a crash with an F150 pickup that was going at speed.

Usually, only the bony spikes remained on other armored dinosaur fossils, because keratin (dead cells that form structures like hair and fingernails) doesn’t fossilize well. So when paleontologists studied armored dinosaurs in the past, they assumed the main protection came from the bony structures, which they thought might have been covered by a thin layer of keratin like a turtle shell.

In 2017, an exceptionally well-preserved fossil was discovered in a mine in Alberta, Canada. The fossil was so well preserved that researchers could analyze the color of its armor and even look into its stomach to see its last meal.

There was a keratin layer over the bones, but it was much thicker than anticipated. It was over 6 inches thick in some places. The keratin sheath over a modern cattle horn is only 0.6 inches thick. The keratin sheath would allow for flexibility and could easily be removed if it got damaged. It would be like trimming a broken nail instead of needing to heal a broken bone.

This armor could withstand much more force than predators of the time could deliver, which suggests the armor may have been used during fights between males who were vying for female mates.

This research also reveals new insight into dinosaur armor in general. It is likely that other armored dinosaurs also had thick keratin sheaths. And those with armored and weaponized faces and heads were probably using a lot more keratin than is normally modeled.

 

https://www.msn.com/en-us/news/technology/armored-dinosaur-could-withstand-the-impact-of-a-high-speed-car-crash-thanks-to-the-bulletproof-vest-over-its-plate-armor/ar-AA1tHLFo?ocid=hpmsn&cvid=f4e5ca4b3d53413dc221ad6255622e96&ei=63

When Did Humans Reach the Americas?

This question has been simmering in the back of my mind for decades. I’ve given panels on it at science fiction conventions, and I’ve written blogs on the subject before, too. I believe the last blog I wrote about it theorized that an ice-free channel through the North American glaciers of the last ice age opened up about 14,000 years ago. And therefore people who had crossed the Bering landbridge sometime before that were finally able to leave Alaska and find their way south to the plains of central North America. And from there, they could have gone on to populate all the rest of North America, Central America and South America.

But even that might not be right.

The other night, we watched a documentary about fossilized footprints in the White Sands National Park in New Mexico. Although the area is a desert now, during the last ice age, it housed a large lake. The fossilized footprints recorded the presence of Columbian mammoths, great ground sloths, North American camels and horses. And among all those footprints, it is not at all unusual to find lots of human footprints.

Scientists have to work fast to learn all they can from these footprints, because as soon as they are revealed by the wind blowing the sand away, the blowing sand starts to erode the footprints away. For these are not the usual fossils that have been turned into stone. Some of the footprints are impressions in the sand, that had been filled with silt that was finer than the sand around them. Others are outlined with bulging sand indicating the weight of the animal. All of them dried out when the lake dried up, and little has happened to the area to disturb them. Except the blowing wind.

A number of scientists work the site each year, and I was left with the impression that each year presents a new batch of footprints, at a slightly lower level than the year before.

One year—and it didn’t say what year it was—a pair of scientists who are experts at radio-carbon dating dug a trench in the sand, going down through several layers of human footprints. But you can’t radio-carbon date sand; you can only radio-carbon date organic material, like plants or animals. By examining the layers between the human footprints, they were able to find organic material, such as seeds or pollen. They packaged up a number of these samples and took them back to their lab in Denver to date them.

Two years later, the narrator visited them in their lab to ask what kind of dates they had gotten from their samples. They said they had gotten dates between 21,000 and 23,000 years ago! That would have been long before the ice-free trail through the glaciers had opened up!

At the very end of the show, the narrator was talking to another scientist, and wondered how humans could have gotten so far south before the glaciers had started to melt. The anthropologist said they had probably followed the Pacific coastline, starting in Alaska and working their way south. But, he pointed out, the sea level was much lower at that time (as much as 400 feet lower), with so much water tied up in the glaciers, so any settlements they might have established would be underwater now. He suggested we should be doing more diving along the coastline to find them.

Okay. Who still thinks that ancient alien visitors brought a herd of humans to the Americas? (This was the last suggestion I made when I gave this talk at conventions.)

Devonian Period

 The Devonian Period spanned about 60 million years of the Paleozoic, from 419.2 million years ago to 358.9 million years ago. It is sandwiched between the Silurian Period, which came earlier, and the Carboniferous Period, which is more recent.

The first significant  adaptations of life on dry land occurred during this period, for life was well underway in colonizing the land. Moss forests and bacterial/algal mats of earlier were joined early in the period by primitive rooted plants that created the first stable soils and harbored such arthropods as mites and scorpions. By far the largest land organism at the beginning of this period was a poorly-understood plant which was possibly the fruiting body of an enormous fungus, a rolled liverwort mat, or another organism of uncertain affinities. This plant stood more than 8 meters (26 ft) tall, which means it towered over the low, carpet-like vegetation that covered the land. The first fossils of insects appeared around 416 million years ago, in the Early Devonian.

Many Early Devonian plants did not have true roots or leaves like modern plants. These were generally very short, growing hardly more than a few centimeters tall. By the middle of the period, forests of shrub-like plants existed, for plants like horsetails and ferns had evolved. These had true roots and leaves, and many were quite tall. Also, the earliest-known trees appeared in the Middle Devonian, although probably not any that we would recognize. Certainly I didn't recognize them from their descriptions, and they all seemed to have 'extinct' in their description. By the end of the Devonian, the first seed-forming plants had appeared. There was such a rapid appearance of so many plant groups and growth forms that it is called the "Devonian Explosion". Various terrestrial arthropods (which includes insects, spiders, and crustaceans) also became well-established.

Fish reached substantial diversity, so that Devonian is often called the Age of Fishes. Among the marine vertebrates, jawless armored fish declined in diversity, while jawed fish increased in both the sea and fresh water. Early cartilaginous and bony fishes also became diverse in the seas. The first abundant genus of shark appeared during this period. The ancestors of all four-limbed vertebrates began adapting to walking on land, as their pectoral and pelvic fins evolved into legs.

The first ammonites (an extinct specie of mollusc) appeared during the Devonian. Trilobites (which look something like armored roaches), brachiopods (similar to a mollusc) and great coral reefs were common in the seas. The Late Devonian extinction, which started about 375 million years ago, affected marine line severely, killing off—among other things—all trilobites save for a few species.

The Devonian was relatively warm, and probably lacked any glaciers. For this reason, the sea level was high. The temperature gradient from the equator to the poles was not as large as it is today. The weather was also very arid, particularly along the equator. Surface temperature of the tropical seas was probably 86°F in the Early Devonian, but CO2 levels dropped steeply throughout the period, because the newly evolved forests drew carbon out of the atmosphere. By Mid-Devonian, there was a cooling of about 9°F. However, there is evidence that the temperature rose again in the Late Devonian, which may have contributed to the extinction event.

The geography was dominated by the supercontinent Gondwana to the south, Siberia to the north, and the early formation of Euramerica in between. It was a time of great tectonic activity, as Euramerica and Gondwana drew closer together. In the early Devonian, Laurentia and Baltica collided, forming Euramerica, which rotated into the natural dry zone along the Tropic of Capricorn (appromately 23.3° South of the equator). Then the plate of Euramerica and Gondwana started to meet, beginning to form the supercontinent Pangaea. This raised the northern Appalachian Mountains and formed the Caledonian Mountains in Great Britain and Scandinavia. The west coast of Euramerica was low lying, with deep silty embayments, river deltas and estuaries (found today in Idaho and Nevada). However, a volcanic island arc approached the west coast in the Late Devonian, and began to uplift that coast in a prelude to mountain-building that happened later.

Hey, we're getting somewhere! If trees and tall bushes could grow during this time period, then the soil must be decent, right? So maybe we could grow crops, so long as we bring our own seeds. And maybe we could set up a farm with some barnyard animals, too, like chicken, ducks, cows and goats. There's insects for the fowl to eat. Do you think cows and goats would eat horsetails and liverworts? Because the article didn't say anything about grasses. And as long as we don't go swimming in shark-filled waters, I think we'd be relatively safe.

 

https://en.wikipedia.org/wiki/Devonian

Cambrian Period

 The Cambrian Period was the first geological period of the Paleozoic Era. It lasted 55.6 million years, from 541 million years ago to 485.4 million years ago. The Cambrian is known for sites of exceptional preservation where even 'soft' parts of organisms are preserved, so our understanding of the Cambrian biology surpasses that of some later periods.

A profound change in life on Earth happened during the Cambrian Period, in that mineralized multicellular organisms became common. The rapid diversification of life-forms in this period—known as the Cambrian Explosion—produced the first representatives of all modern animals, probably from a single common ancestor.

Although life prospered in the oceans, the land is thought to have been comparatively barren. Shallow seas flanked several continents and were relatively warm. Polar ice was absent for much of the period.

Large, high-velocity rotational movement of Gondwana appears to have occurred in the early Cambrian, and may have resulted in Laurentia (North America), Baltica and Siberia being 'tossed away' and forming isolated land masses. Most continental land was clustered in the Southern Hemisphere, but was drifting north.

With a lack of sea ice, the sea level was high, which led to large areas of the continents being flooded in warm shallow seas, which were ideal for sea life. The sea levels fluctuated, suggesting there were pulses of expansion and contraction of a south polar ice cap.

The article stated that the Earth was generally cold during the early Cambrian, and then said the average temperatures were 7 degrees Celsius higher than today. That doesn't seem very cold to me.

The Cambrian flora was little different from what had existed in the previous period. Primarily, there were marine macroalgae in the seas, and that was pretty much it. There were no land plants known from the Cambrian, although biofilms and microbial mats were well developed on tidal flats and beaches 500 million years ago. There were also microbes forming microbial Earth ecosystems, comparable with modern soil crust of desserts, which contributed to soil formation.

It was once thought that trilobites were the dominant life form of the time period. But it turns out that these had a heavy armor which fossilized far more easily than the bodies of other animals, so there were plenty of trilobite fossils, even though trilobites were only a minor part of the animal diversity.

Earth suffered a mass extinction at the start of the Cambrian Period. It is thought that animals that burrowed into the sea bed, destroyed the microbial mats covering the seabed, and many organisms dependent on the mats became extinct, while other species adapted to the changed environment.

Despite the 'Explosion' at the start of this period, the later half saw a sharp drop in biodiversity. 500 million years ago, oxygen levels in the oceans dropped dramatically, while the level of poisonous hydrogen sulfide increased, producing more extinction events, making the latter half of the period surprisingly barren.

However, some organisms did venture onto land, producing trace fossils of their movements. Some of these fossil trackways suggest a large, slug-like mollusc.

Just when you thought Earth pre-history was going to get interesting, it takes one step forward and two steps back. Dry land is still pretty barren, except for an occasional slug-mollusc looking for some tasty soil microbes.

Well, we're pretty sure humans arrive on the scene eventually, so we're just going to keep slogging forward until we find us.

 

https://en.wikipedia.org/wiki/Cambrian

Tonian, Cryogenian, and Ediacaran Periods

Tonian Period

The first section of the Neoproterozoic Era is the Tonian Period. It lasted from 1,000 million years ago to 720 million years ago. The breakup of supercontinent Rodinia began around 900-850 million years ago.

The first large evolutionary radiation of organic microfossils occurred during the Tonian Period. This means a huge increase in diversity caused by a large rate of specialization. None of the examples in this article of evolutionary radiation were from the Tonian period, however, probably since it involved microfossils, which most lay people are not terribly familiar with.

So, Rodinia started breaking up, and microorganisms multiplied and diversified. It still sounds like a pretty barren place to me.

Cryogenian Period

The second geologic period of the Neoproterozoic Era was the Cryogenian Period, lasting from 720 to 635 million years ago. There were 2 ice ages during this period, the Sturtian and Marinoan Glaciations, which are said to be the greatest ice ages known on Earth. There is much debate over whether these glaciations covered the entire planet (Snowball Earth) or a band of open sea survived near the equator (Slushball Earth).

In any case, the Sturtian Glaciation lasted from 720 to 660 million years ago, while the Marinoan Glaciation ended at approximately 635 million years ago, although there was no indication when it began. Whenever it began, it was relatively short-lived when compared to the Sturtian.

Fossils of hard-shelled amoeba first appear during this period, as well as the oldest known fossils of sponges. Debate about how much the glaciation might have impacted biology rages on, with some suggesting that several species began during this period.

Me, I much prefer warmer climes.

Ediacaran Period

The end of the Era is marked by the Ediacaran Period, which lasted from 635 million years ago to 541 million years ago.

Fossils from the Ediacaran are sparse, as not a lot of hard-shelled animals had yet evolved. But there were multicellular organisms with specialized tissues. The most common types resemble segmented worms, fronds, disks, or immobile bags. Although Ediacara biota bear little resemblance to modern lifeforms, more than 100 genera have been described.

During this period, the moon was considerably closer, making the tides stronger and more rapid than they currently are. A day was about 21.9 hours long, meaning there were about 13.1 months per year, and approximately 400 days/year.

Okay, now we're getting somewhere. The place had worms and fronds, or at least lifeforms that looked like them. I was particularly pleased with the information about the days being shorter and the moon being closer. How long do you suppose it would take human colonists to get used to a 22-hour day instead of a 24-hour day?

 

https://en.wikipedia.org/wiki/Tonian#:~:text=The%20Tonian%20(from%20Greek%20%CF%84%CF%8C%CE%BD%CE%BF%CF%82,Mya%20(million%20years%20ago).&text=The%20Tonian%20is%20preceded%20by,and%20followed%20by%20the%20Cryogenian.

https://en.wikipedia.org/wiki/Evolutionary_radiation

https://en.wikipedia.org/wiki/Cryogenian#:~:text=The%20Cryogenian%20(%20%2Fkra%C9%AA,and%20followed%20by%20the%20Ediacaran.

https://en.wikipedia.org/wiki/Ediacaran

  

Calymmian, Ectasian & Stenian Periods

 

Calymmian Period

There are 3 periods in the Mesoproterozoic Era. However, the article on the first of these periods, the Calymmian Period, was less than 100 words long. The Calymmian Period lasted from 1600 to 1400 million years ago. During this time, the continents expanded by adding sedimentary flatlands. Right in the middle of the period, the supercontinent Columbia started to break up.

 

Ectasian Period

The 2nd period is the Ectasian Period, which in Greek means “extension”. It lasted from 1400 to 1200 million years ago. The name refers to the continued expansion of sedimentary flatlands.

Fossils have been found dating from this period that provide the first evidence of sexual reproduction. This allowed and was necessary for complex multicellularity, in which certain cells of the organism are specialized to perform different functions.

 

Stenian Period

The Stenian Period is the final segment of the Mesoproterozoic Era, lasting from 1200 to 1000 million years ago. The supercontinent Rodinia assembled during the Stenian.

And the Keweenawan Rift formed at about 1100 million years. This rift (tear) occurred in the middle of the North American continent. I had never heard of this rift before. One wonders if North American was much skinnier before the rift occurred and the rift has been filled in since then. If that were the case, the rift could have been as small as the Mississippi River valley, or it could have stretched from the Rocky Mountain foothills to the Appalachian foothills, if those existed at that time. What would have happened if the rift had grown and deepened. Would we have 2 continents where we only have 1?

A closer look at the map provided showed it to be a lop-sided horse-shoe-shaped rift. The 2 ‘arms’ meet at Lake Superior, which defines the northern arc of the rift. The eastern arm trends south into lower Michigan, and possibly as far south as Alabama. The western arm runs southwest into Kansas and possibly as far as Oklahoma. A northern arm, which was not shown on the map, ran up into Ontario and formed another lake, but didn’t go any further.

So, let’s see, if that 3-armed rift had actually grown and spread, we might have had 3 continents where we now only have 1. That would certainly change things up. Now I have alternate histories running rampant through my mind. What do you think about that? Eastern North America, Western North America and a Mexico that reaches Lake Superior.

 

https://en.wikipedia.org/wiki/Calymmian

https://en.wikipedia.org/wiki/Ectasian

https://en.wikipedia.org/wiki/Stenian

https://en.wikipedia.org/wiki/Midcontinent_Rift_System

Mesoarchean & Neoarchean Eras

 Mesoarchean Era

We will continue studying the Archean Eon with a brief look at its 3rd part, the Mesoarchean Era. How brief a look? That will depend on how much I find.

The Mesoarchean Era lasted from 3,200 to 2,800 million years ago. There is no specific level in the rocks that designates this era, it is simply defined by the time period.

Fossils from Australia prove that stromatolites have been growing on Earth since the Mesoarchean Era. These sedimentary formations are created by photosynthetic cyanobacteria that produce adhesive compounds and cement sand and other rocky materials into mineral “microbial mats”. These multi-layered sheets of microorganisms, mainly bacteria, grow at interfaces between different types of material, mostly on submerged or moist surfaces. They have been known to colonize environments ranging in temperature from -40C to 120C (about -48F to 272F). The mats grow layer by layer and can grow to a meter or more. Although uncommon today, fossilized stromotalites record ancient life on Earth. The earliest reefs, probably formed by stromatolites, date from this era.

The article had a tantalizing statement about the Pongola glaciation occurring around 2,900 million years ago but a brief search couldn’t find any more information about it. Was it only at the poles, or was it world-wide?

At the end of this era, the first supercontinent broke up, right about 2,800 million years ago.

 

Neoarchean Era

That brings us to the 4th part of the Archean Eon, the Neoarchean Era,  from 2,800 to 2,500 million years ago. Again, this era is defined only by time, not to a specific rock level.

During this era, oxygenic photosynthesis released an abundance of oxygen, which first reacted with minerals and afterward was free to react with greenhouse gases of the atmosphere. By reacting with these greenhouse gases, the oxygen changed them into gases that trapped less heat in the Earth’s atmosphere, and the Earth began to cool off. Eventually.

Remember the microbial mats from the Mesoarchean Era? Did I mention these mats were created by cyanobacteria? Cyanobacteria give off oxygen as a waste product. We should celebrate the ancient existence of cyanobacteria as the provider of the oxygen that we need in order to live.

However, back then, what life existed could not use oxygen. In fact, it was poisonous to most forms of life of the time. So when O2 levels got too high, a lot of the existing life died off. But that happened later. The process that led to that problem was only beginning during the Neoarchean Era.

Also during the Neoarchean Era, at about 2,720 million years ago, the supercontinent Kenorland formed.

 

https://en.wikipedia.org/wiki/Mesoarchean

https://en.wikipedia.org/wiki/Stromatolite

https://en.wikipedia.org/wiki/Microbial_mat

https://en.wikipedia.org/wiki/Neoarchean

Eoarchean & Paleoarchaen Eras

 Eoarchean Era

The Archean Eon is divided into 4 eras, the first of which is the Eoarchean Era. This era began immediately after the Hadean Eon 4 billion years ago, when the Earth had cooled enough to have a solid crust. However, this crust may have been incomplete, with lava flowing at many sites at the surface.

In addition, the beginning of the Eoarchean Era saw heavy bombardment of the inner solar system by asteroids. The oldest rock formations yet discovered occur in Greenland and Canada. The former has been dated to 3.8 billion years old, and the latter 4.031 billion years old.

The Eoarchean Era ended 3.6 billion years ago. The earliest forms of life began within this era. The atmosphere had no oxygen and the atmospheric pressure was from 10 to 100 times what we feel now.

Man, that is a lot of atmosphere. And not a bit to breathe. I mean, you could breathe it, but without any oxygen, breathing wouldn’t do you any good. And the article said life got started at this point, but they didn’t even give that life a name for me to do further research. Well, it was a long time ago, when things on Earth were still pretty... unsettled.

 

Paleoarchaen Era

The next era of the Archean Eon is the Paleoarchaen Era. Not a lot to report on here, either, as this article was even shorter than the one on the Eoarchean Era.

The Paleoarchaen Era started 3.6 billion years ago and ended at 3.2 billion years ago. There are no big happenings at either end to mark the changing of eras, it is simply a convenient way for scientists to refer to this section of the Earth’s history.

The oldest confirmed form of life is fossilized bacteria in microbial mats, approximately 3.480 billion years old and found in Australia.

This is when the first supercontinent formed, and if you remember from my earlier blogs, that would either be Ur or Vaalbara, depending on which one your college professor prefers. There is firm belief that there was one at this time, but there is some debate over the name, and exactly what pieces of crust fit where in it.

Also during this era, a large asteroid, about 23-36 miles wide, collided with the Earth in the area of South Africa. This was approximately 3.26 billion years ago, and created the Barberton greenstone belt.

I can’t help but wonder how that managed to happen. Ur/Vaalbara may have been the supercontinent of the time, but it only held about 12-15% of the continents we currently have. Math says that that ‘supercontinent’ would have covered less than 5% of Earth’s surface. How did a random asteroid just happen to hit that?

I didn’t see anything different regarding the atmosphere, so I’m assuming it was much the same as during the Eoarchean Era. Keep holding your breath. Sooner or later, oxygen starts.

 

https://en.wikipedia.org/wiki/Eoarchean

https://en.wikipedia.org/wiki/Paleoarchean

Ichthyosaurs

 

Ichthyosaur is Greek for ‘fish lizard’, and is the name for a group of large extinct marine reptiles. They lived during the time of the dinosaurs, but formed a separate group from them and may not have been closely related.

Ichthyosaurs thrived during much of the Mesozoic era. Based on fossil evidence, they appeared about 250 million years ago, and at least one species survived until about 90 million years ago, during the Late Cretaceous. During the early Triassic period, ichthyosaurs evolved from some unidentified land reptile that returned to the sea. In a case of convergent evolution, they gradually came to resemble modern dolphins and whales, which evolved from land-dwelling mammals millions of years after the ichthyosaurs returned to the ocean. These ‘fish lizards’ were abundant until the later Jurassic and Cretaceous periods, when they were replaced as the top aquatic predators by the Plesiosauria, another marine reptilian group.

Ichthyosaurs averaged 2-4 meters (6.6 to 13.1 ft) in length. Some specimens were as short as 1 ft, while other species were much larger. During the Triassic, the Shonisaurus popularis was about 15 meters (49 ft) long. The Shastasaurus sikanniensis was estimated in 2004 to have been 21 meters (69 ft) long. Some lower jaw fragments found in England indicated a length between 20 and 25 meters (66 to 82 ft).

Weight estimates indicate a 2.4 meter (8 ft) Stenopterygius weighed around 163-168 kg (359-370 lb), while a 4 meter (13 ft) Ophthalmosaurus icenicus weighed 930-950 kg (2,050-2,090 lb). That would be a lot of tuna! Or salmon.

The earliest members of the ichthyosaur lineage were eel-like, but later members resembled more typical fishes or dolphins. Their limbs had been fully transformed into flippers, and some species had a fin on their backs and a more vertical fin at the rear of a rather short tail.

Their heads were pointed, and the jaws often came equipped with conical teeth to catch smaller prey. Some species had larger, bladed teeth to attack large animals. Their eyes were very large and the neck was short. Later species had a stiff trunk with a more vertical tail fin, which made for a powerful propulsive stroke. Ichthyosaurs were air-breathing, warm-blooded and bore live young. It’s possible they had a layer of blubber for insulation.

They may have looked like fish, but they were not. They were reptiles. They adapted so well to their environment that some of them developed dorsal fins and vertical tail fins without their ancestors having had anything there to be adapted.

 

https://en.wikipedia.org/wiki/Ichthyosaur

Whale Ancestors

Where did whales come from? How did a fish evolve to become as large as a modern whale?

Actually, whales took a round-about route to evolve into today’s huge ocean creatures. They are actually descended from a land animal.

There are plenty of clues in a whale’s body and biology that their ancestors lived on land:

* They breathe air.

* They nurse their young with their own milk.

* Their paddle-shaped flippers encase hand bones with five ‘fingers’.

* As embryos, whales have tiny back limbs which disappear before birth.

It turns out that hippos are the closest living relatives of whales, but not their ancestors. Both hippos and whales evolved from four-legged, even-toed, hoofed ancestors that lived on land about 50 million years ago. The hippo’s ancestor stayed on land, but the whale ancestor—which was about the size of a goat—moved to the sea and evolved into swimming creatures over a period of about 8 million years, which is quite fast for evolutionary processes.

When fossils of gigantic ancient whales were first discovered, they were mistaken for dinosaur fossils and given the name Basilosaurus. But later, they were recognized as mammals. These prehistoric whales were more elongated than modern whales and had small back legs and front flippers. Their nostrils were situated halfway between the tip of the snout and the forehead. They had earbones just like those of modern whales. Therefore, Basilosaurus showed the link between whales and their terrestrial ancestor.

The current theory is this: That some land-living hoofed animals favoured the flavor of plants at the water’s edge. Eating them had the added advantage of allowing them to easily hide from danger in shallow water. Over time, their descendants spent more and more time in the water, possibly in an ancient estuary, and their bodies became adapted for swimming. The front legs became flippers. A thick layer of fat called blubber replaced their fur coats to keep them warm and streamlined. Their tails became bigger and stronger for powerful swimming, and their back legs shrunk. Their nostrils gradually moved to the top of their heads so that they could breathe easily without having to tilt their heads while swimming. As these creatures began to feed on a different diet, they lost their teeth in favor of a baleen filter method of feeding.

Between these articles, there was some disagreement about what whale ancestors ate. One stated that they favored plants found at the water’s edge. Another felt they ate small land animals and fish found close to shore. Neither article had any information on the teeth whale ancestors had, so their eating preferences seem pretty much up in the air.

So, what can we learn from this tale of whales? Be careful what and where you eat? Evolution is your friend? I find myself wondering if whales would ever come back out of the water, what would they evolve to then? Some version of a goat-sized, hoofed animal again? One of the articles did mention that occasionally, a whale comes along that does have vestigial back legs that are completely encased within their body. Therefore, it seems possible that back legs could make a comeback.

Come on, work with me here. If octopuses can come out of the ocean and become a terrestial bad guy, as some scientists seem to think, then surely whales can also emerge from the oceans. Given enough time to evolve.

 

https://us.whales.org/whales-dolphins/how-did-whales-evolve/

https://evolution.berkeley.edu/evolibrary/article/evograms_03

https://www.nhm.ac.uk/discover/when-whales-walked-on-four-legs.html

Velociraptors

Velociraptors lived about 75 to 71 million years ago. There are 2 known species, both from Mongolia. The second species was only discovered in 2008.

They were depicted in the Jurassic Park movie as swift bipedal reptiles with a long tail and an enlarged sickle-shaped claw on each hindfoot, 6 1/2 feet tall and weighing about 180 pounds. Not so, say the scientists. They were bipedal reptiles, they were fast, and they had the fearsome claw. But they also had feathers, and were actually the size of a turkey. The raptors depicted in the movie series were based on a related genus, because the script said they had to look suitably fierce.

Instead of being 6.5 feet tall, velociraptors were as much as 6.75 feet long, snout to tail tip. Scientific artistic renditions show a very long, feathered tail. They were about 1 ft 7 inches high at the hip and weighs about 33 lbs. Although bipedal, their body and tail were roughly parallel to the ground. Their forefeet were also feathered, but were too short to serve as wings.

Their skulls grew up to 10 in long. The jaws were lined with 26-28 widely-spaced, serrated teeth on each side, more strongly serrated on the back edge than the front.

Their hands were large, with 3 curved claws. However, the structure of the wrist bones forced the hands to be held with palms facing inwards and not downwards.

On their feet, the first toe was a small dewclaw, and the 2nd held the ferocious claw spoken about earlier, which could get 2.5 inches long along its outer edge. Only their 3rd and 4th toes were used in walking or running. Although some beliere their 2nd toe claw was used for disemboweling prey, tests have proven it was most likely used for stabbing and holding, to keep their prey from escaping.

If we’re going to compare fiction to fact, then we must consider the depiction in the Jurassic Park movies of velociraptors hunting in packs. Although there are some indications of other species in the family hunting in packs, there is little to no indication in the fossils of velociraptors doing it.

Most of the known velociraptor fossils have been found in current desserts, under conditions that indicate the locale at the time of their death was also arid and covered in sand dunes, or possibly a little less arid.

Now, my first thought about incorporating velociraptors in a story involves a comedy-ish story where a town in the desert is suddenly overrun by predatory turkeys, which turn out to be—according to the local Wise Guy—descendants from velociraptors, long thought extinct these millions of years. Of course, once the raptors ate up all the local cats, dogs, and chickens, they would necessarily start picking on larger prey... large dogs, wolves, goats... children? Alas, I don’t do horror, which is where this thought is quickly leading me. Anybody out there have any other ideas?

https://en.wikipedia.org/wiki/Velociraptor

https://www.livescience.com/23922-velociraptor-facts.html

https://www.nhm.ac.uk/discover/velociraptor-facts.html

Rhynchosaurs

Imagine a reptilian pig with a hammerhead, no visible ears, and a parrot-like beak, and you'll have a pretty good mental picture of a rhynchosaur.

Rhynchosaurs were herbivores that in some fossil localities account for 40 to 60% of the specimens found, making them the most abundant plant eaters on land. They were reptiles with stocky bodies and a powerful beak.

Early forms were small, less than a meter long, and typically lizard-like in build. They had narrow, wedge-shaped skulls with a few small, blunt teeth for eating plants.

Later versions grew up to two meters in length. The skull in these later forms were short, broad and triangular, becoming much wider than long, giving them a somewhat hammer-head appearance, although the eyes were set close together, near the top of the beak. The broad skull accommodated powerful jaw muscles that enabled the rhynchosaurs to cut up tough plant material. The teeth were modified into broad tooth plates, and the lower jaw fit into a groove on the upper jaw, enabling the ‘cutting’ of plant fibers.

The hind feet were equipped with massive claws, presumably for digging up roots and tubers, although digging claws are usually found on the front feet. Like many animals of their time, they spread all across Pangea, and thus across the world.

And that seems to about all there is to say about the rhynchosaurs. They lived during the Triassic era (251 to 199 million years ago), dying out just before herbivore dinosaurs appeared.

I think I would have found rhynchosaurs terrifying, particularly the larger ones, even though they were basically reptilian cows or deer. Let’s face it, the larger ones were as long as a man is tall, and who’s to say they wouldn’t try munching on this new plant called human that invaded their space, even if it didn’t sit still like other plants?

What do you think? If you had a time machine, would you venture back to visit them up close and personal?

 

https://ucmp.berkeley.edu/taxa/verts/archosaurs/rhynchosauria.php

https://en.wikipedia.org/wiki/Rhynchosaur

Nimravs

I couldn’t help but look up Nimravidae; the name reminded me of ‘nimrods’, which of course have nothing to do with Nimravidae. Naturally, I didn’t know that until I looked it up.

The Nimravidae were a cat-like creature whose fossils have been found in North America and Eurasia. They are sometimes called ‘false saber-toothed cats’. They existed from about 40.4 million years ago to 7.2 million years ago, spanning some 33.2 million years.

It is thought that the ancestors of nimravids and cats diverged from a common ancestor about 50 million years ago. Nimravid diversity appears to have peaked about 28 million years ago before the family began a slow descent into extinction. This diversity was apparent in the size and shape of their teeth, as well as the size of the body. Some nimravidae were the size of modern lions, and they had various other smaller sizes down to the size of a small bobcat. Their legs and tails were proportionally shorter than those of true cats.

When nimravid first appeared, the global climate was warm and wet, but it trended cooler and drier shortly after that. This meant the lush forests were transforming to scrub and open woodland, where the nimravids flourished. North America and Asia were connected at the time, and they inhabited both. Europe was more of a cluster of islands rather than a continent at the time, but there must have been some land bridges, for the nimravids also found their way there.

Still later, the woodlands were replaced by savanna in North America and Asia, and the nimravids in those areas died out. Portions of humid forests continued in Europe for a time, but when those died out in the late Miocene, so did the rest of the nimravids.

One has to wonder if the saber-tooth tiger that Fred Flintstone put out of the house every evening was really a saber-tooth tiger or actually a nimravidae.

On second thought, there may be a tenuous connection between ‘nimrod’ and ‘nimravidae’. The dictionary tells me that ‘nimrod’ refers to a person who is good at hunting. As a carnivorous species, the nimravidae had to be good at hunting. Now I wonder if that influenced whoever named this family of creatures. Or what exactly does ‘nimravidae’ mean in whatever language they used to construct this name?

  

https://en.wikipedia.org/wiki/Nimravidae

https://www.britannica.com/animal/Nimravidae

Jonah in a Basilosaurus

Okay, probably not what happened, because we are talking about an extinct species here. Basilosaurus means “king lizard” and it is a genus of large, predatory, prehistoric whale, living from approximately 41.3 to 33.9 million years ago. It was first described in 1834, based on fossils found along the Gulf Coast of the US, along with a few fossils in the eastern US. It was thought to be a giant reptile, hence the -saurus ending to the name. They were later discovered to be an early marine mammal, but it was too late to change the name.

 Likewise, the genus Basilosaurus was something of a wastebasket for odds and ends of fossils that nobody thought belonged anywhere else. But most of those have been removed and placed in more correct classifications, leaving 2 species in this genus.

 Unlike modern whales, who swallow their food whole, the Basilosaurus had various types of teeth, such as canines and molars, so it probably chewed it food. It was the top predator of its environment, preying on sharks, large fish and other marine mammals, such as another early whale, the Dorudon, which seems to have been their predominant food source.

 At a size of 49-66 ft (15-20 m), Basilosaurus  is one of the largest known animals existing from 66 million to 15 million years ago. Basilosaurus Isis is  slightly smaller than Basilosaurus Cetoides by about 7 feet.

 Basilosaurus appear to be closely related to even-toed ungulates, such as giraffes and buffalo. Does that mean it was a land animal that reverted to living in the sea? I don’t know.

 It is not believed that Basilosaurus could produce high-frequency sound and echolocation, which some modern whales can do.

 Studies of a complete skeleton fossil as well as overlapping skeletal reconstruction indicate Basilosaurua had about 70 vertabrae. They were shaped much like eels, and probably moved much like eels as well, mostly at or near the ocean’s surface, as they do not appear to have had a method for diving.

 So, if a person by the name of Jonah had been at sea during the time period, I suppose he could have been eaten by a Basilosaurus. But living through being eaten would have been problematic, since the Basilosaurus would have chewed before swallowing

 Since these were marine mammals, I suppose their ancestors were land mammals that - for whatever reason - decided to return to the water. And other branches of the family went on to become giraffes and buffalo, among others? What a family tree!

 

 

https://en.wikipedia.org/wiki/Basilosaurus

Quetzalcoatlus

If you think the name looks a lot like the name of the Aztec feathered god, you are right. the fossils of this winged reptile were named after that god. This type of pterosaur is the largest known example of flying animal. The artist’s rendition that was intended to give some clue as to size showed a standing quetzalcoatlus just as tall as a giraffe (with a neck just as long), and a wing span of about 36 feet (11 m). The human man in the picture was not quite as tall as the back legs were long.

As I read the article, I was reminded again and again of the ‘airplanes’ in the Flintstones cartoons, where a small cabin sat atop a huge flying reptile. Not very feasible, as even this huge creature would probably be able to carry only 2-3 humans on its back. And I don’t know if it could fly with that much extra weight.

The skeleton pictures showed a skull that was mostly beak, with a bony crest on the forehead, between the large eyes. It doesn’t have any teeth, and its wings are depicted as looking quite a bit like a bat’s wing. It is also depicted as folding its wings in half and possibly using its wings as support when standing or walking. Most of the known fossils of this creature were found in Texas.

Several feeding patterns have been suggested for the Quetzalcoatlus, but the most recent one is that they stalked small vertebrates while on the ground, similar to the modern stork.

There has been much argument among scientists about Quetzelcoatlus’ ability to fly. The latest thought is that they would use powered flight to get to a point where they could use thermal gliding. The wing muscles were found to be quite robust, which they would not be if the animal were purely a terrestrial animal.

There are potentially 2 species of Quetzelcoatlus. Measurements I’ve given are for the larger specie, there is possibly another specie that is about half as large.

So, if this extinct species comes back to life, that could make life difficult for the human population. While adults might be too large for the smaller Quetzelcoatlus to attack, children would probably be seen as ‘fair game’. And even adults might have to watch out if the larger variety is around.

https://en.wikipedia.org/wiki/Quetzalcoatlus

Extinction Event 1

We all know the dinosaurs went extinct. Okay, most of them. But that was not the first ‘Great Extinction Event that Earth has suffered. Since I’m really only aware of that one and its possible cause, I decided to investigate the first one, just to see what I could find. Apparently, it was caused by oxygen!

I know, right? Something we think is a good thing, yet it caused a massive die-off! How could this be? Let’s take a look.

First, let’s be sure we understand what an extinction event is; it is a widespread and rapid decrease in the biodiversity on Earth. Estimates of how many extinction events we’ve already had range from 5 to as many as 20.

Most life on Earth is microbial and thus difficult to measure. Therefore recorded extinction events are those that affected the easily observed, biologically-complex component of life on Earth. Normally, extinction of various lifeforms occur at an uneven rate. An Extinction Event is when a lot of different lifeforms go extinct at pretty much the same time.

The Oxygenation Crisis occurred around 2.45 billion years ago, but technically, as I studied it further, it is not considered one of The Great Extinction Events. Maybe because it’s hard to find fossils from that long ago, so they can’t be sure what died off and in what numbers, but it was big enough that the fossils they have found indicate something happened.

From what I understand, Earth’s atmosphere at the time had next to no free oxygen in it. But then photosynthesizing cyanobacteria (which some call blue-green algae) evolved in the shallow sea that covered most of Earth. The cyanobacteria did what it does, and in the process, released free oxygen into the water. Eventually, the water couldn’t hold any more of it and released free oxygen into the air. All this free oxygen (which was a mere pittance compared to what we currently have in our atmosphere) played havoc with the metabolism of most of the living organisms at the time and a great deal of them died.

And the cyanobacteria continued putting out more oxygen.

Which opened the gates for more complex biolife forms.

So, extinction events are not always a bad thing... if you aren’t a species that is going extinct. But they do tend to create ‘bottle-necks’ of survival, which are followed by much evolving and diversification to fill all the empty niches that result.

https://en.wikipedia.org/wiki/Extinction_event