Archive for January, 2014

Musk-oxen are More Closely Related to Goats than They are to Cows

January 29, 2014

In one of the first articles I ever wrote for this blog, I speculated there were 3 species of Pleistocene bovines roaming the area known today as Georgia.  Bison antiquus, a late Pleistocene species of bison, is thought to have evolved from Bison latifrons about 24,000 years BP, yet  a specimen of the latter found in Clark Quarry near Brunswick, Georgia suggested there was a temporal overlap between these 2 species. This specimen  was originally dated to 14,000 BP.  Since I wrote that article, scientists have resubmitted this specimen to radiocarbon dating. and this time it produced a date of 24,000 BP–within the accepted time span this species is thought to have existed.  It’s still one of the more recent specimens of this species, but it is not evidence of temporal  overlap with B. antiquus. There was never more than 1 species of bison living in the region at the same time.

About a month ago, a reader also alerted me to an error I made by classifying the helmeted musk-ox (Bootherium bombifrons) as a bovine.  I wrongly assumed because of its appearance, and the common name ox, that it was closely related to cows. An oxen is a word used for a castrated cow. I should have paid closer attention to my mammalogy books.  Musk-oxen are more closely related to goats and sheep than they are to cattle.  Many laymen likely share my misconception, so I’ve reviewed the literature and will now sort out the bovids.

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Woolly musk-oxen are like a really large goat and are not close kin to cattle.  A species of musk-oxen adapted to temperate climates  lived as far south as Louisiana during the Iice Age.  It was taller, had shorter hair, and a different horn structure than the species  still extant.

Photo: A mountain goat sitting on top of a mountain

Mountain goats are in the same subfamily as muskoxen.

Saiga antelope are also in the same subfamily as musk-oxen.  During the Ice Age saiga antelope lived as far east as Alaska.
The Bovidae family is divided into 2 subfamilies: the caprinae and the bovinae.  Bovids originated in Africa and most species are adapted to warmer climates, but during the Pleistocene a number of species became adapted to the cooler climates of the Ice Ages, and they spread throughout northern Eurasia and across the Bering Landbridge to North America.  None ever made it to South America.
Pleistocene and modern American species in the caprinae subfamily include saiga antelope (Saiga tatarica), shrub oxen (Eucatherium sp.), mountain goats (Oreamnos americanus), Harrington’s mountain goat (Oreamnos harringtoni), bighorn sheep (Ovis Canadensis), dall sheep (Ovis dalli), woolly musk-oxen (Ovibos moschantus), and the helmeted musk-oxen (Bootherium bombifrons)..  The  bovinae species that colonized North America were bison (Bison sp.), and the yak (Bos grunniens), the latter having been restricted to mountains in Alaska during some climate stages of the Pleistocene.
Saiga antelopes still occur on central Asian steppes, but they expanded their range to the grassy mammoth steppe of Alaska during the Last Glacial Maximum.  Shrub oxen were probably the first bovids to colonize North America early during the Pleistocene, and they didn’t become extinct til about 11,000 BP.  Shrub oxen are not known to have occurred east of Iowa.  Harrington’s mountain goat was a sister species of the modern day mountain goat and is also now extinct.
The only species of caprinae that ever colonized southeastern North America was the helmeted musk-ox.  Fossils of this species have been found in Texas, Lousiana, Mississippi, western Tennessee, and Virginia; but notably not in the abundant fossil deposits of Florida. (See https://markgelbart.wordpress.com/2011/07/27/the-south-central-salient-of-the-helmeted-musk-ox-ovibos-cavifrons-or-bootherium-bombifrons/ )  This suggests the southeasternmost range limit was in north or central Georgia or possibly South Carolina’s piedmont.  The helmeted musk-ox expanded its range during the Last Glacial Maximum when grassy desert scrub habitat became a widespread type of environment throughout North America.  Fossil coprolites, originally excreted by helmeted musk-oxen, show these tough animals fed upon green vegetation during summer but could subsist on dry twigs during the long cold Ice Age winters.  Like their goat cousins, they could absorb nutritional value from dead plant material, reminding one of the cartoon stereotype of goats eating the wrappers off tin cans. This amazing animal was able to extract nutrition from cellulose.
Because helmeted musk-oxen were able to survive on dry twigs, I do not believe climate change could have caused their extinction.  There has never been a shortage of dry twigs in North America during any climate phase.  I do believe the replacement of their favored habitat of desert scrub and grassland with forests and woodlands following the end of the Ice Age did cause the range of this species to contract.  This range contraction made them more vulnerable to human overhunting.  Like wooly musk-oxen, the helmeted musk-ox formed defensive circles when confronted with predators.  This was effective against wolves or saber-tooth cats but disastrous against spear-wielding humans who could slaughter an entire herd at once from a safe distance.  R. Dale Guthrie speculated competition with bison caused the extinction of helmeted  musk-oxen, but I reject this hypothesis because these 2 species co-existed for 300,000 years.  I believe bison avoided extinction because they run away from people and migrate long distances and perchance found regions where the population of humans was too low to eat them faster than they could reproduce.

Bald Eagle’s Nest on Berry College Campus

January 24, 2014

It has been decades since I’ve seen a wild bald eagle (Haliaeetus leucocephalus)  in person.  A pair of bald eagles began nesting on Berry College Campus in Rome, Georgia within the last 2 years, and a crew set up a camera that sends a live feed of the birds to the internet. (See http://www.berry.edu/eaglecam/)  Everytime I click on the link, the mother bird is incubating the eggs.  I have yet to see the male.  I visited the campus the other day, hoping I might see either the male or female in flight.  The directions on the campus website stated the nest was between the Steven Cage Athletic Center and the campus entrance, so I parked in front of that building and began triangulating between there and the entrance.  I saw the nest and approached.  I heard an anxious man’s voice:

“Are you authorized to be there?” the anxious do-gooder asked.

“Are there signs?” I asked, guessing from the tone of his voice that the area must be prohibited.

“Here, here, and here,” the do-gooder smart aleck pronounced, as if I was an idiot unable to see the 3 closely planted  signs.

I looked over and saw a small crowd pointing at the eagle’s nest 100 yards from them.  I had approached from a different angle–it wasn’t the frontal assault the campus officials expected the enemy to make.  The campus folks need to spread their signs out, if they want to keep birders 100 yards away from this nest.  Otherwise, their defenses  will  get outflanked.

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The bald eagle’s nest on Berry College campus is at the top of the middle tree in this photo I took.  Some day, I will stop being cheap and purchase a telephoto lens.

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This is the plaque about 100 yards in front of the eagle’s nest.  People aren’t allowed to advance any closer than this to the tree.

Eagle nests are very large, and they are re-used over the bird’s lifespan which can be 30 years.  Each year, the birds add more material, and old nests can weigh as much as 4000 pounds. This pair of eagles catch fish and coots from the Oostanaula River and a pond formed by Berry Quarry.  The river is about a mile away from the nest, and on the map it looks like a small oxbow lake is adjacent.  I wonder why the eagles don’t nest even closer to the river.  They supplement their diet of fish with the squirrels, rabbits, and deer carcasses abundantly found on the Berry College Wildlife Management Area.  Perhaps the nest is in a central location that gives them access to multiple sources of food.

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A view of Lavender Mountain from the Viking Trail on Berry College Campus.  This trail is nice for jogging and biking but is botanically uninteresting.  It’s a powerline right of way on the edge of pine tree plantation.

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Oostanaula River.  This is where the bald eagles catch fish.  They must have x-ray vision…the water is so muddy I couldn’t see any fish.

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Sign telling people how to release any Lake Sturgeon they accidentally catch.

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Cute graffiti under the bridge over the Oostanaula River. 

I drove to the Oostanaula River to check out the local eagles’ source of food.   There has been so much rain in Georgia this past month that all rivers and reservoirs have become muddy from erosion.  In the 18th century William Bartram described Georgia’s rivers as pellucid, meaning they were clear as spring water.  But farmers stripped the land of trees and replaced the forests with cotton fields, exposing the soil to wind and rain.  Lumber companies later destroyed more forests.  Today, rampant suburban development has steadily increased the amount of bare soil washed into Georgia’s rivers.  Georgia’s waters were not meant to be this muddy.

There were a lot of squirrels and Canadian geese alongside this part of the Oostanaula River.  River birch and sycamore are the most common trees, and I saw leaves belonging to overcup and Shumard’s oaks–the trees producing the acorns that help support all the squirrels here.  Lake sturgeon (Acipenser fulvescens) have been re-introduced to the Etowah River.  The Oostanaula River joins with the Etowah River to form the Coosa River which flows through Alabama.  Apparently, the lake sturgeon have spread to the Oostanaula because there’s a sign here warning fishermen to release them if caught.

Most people mistakenly believe DDT contamination was the cause of the bald eagle’s near extinction, but this is not at all true.  Until the 20th century, people shot eagles on sight because they believed they were protecting their livestock.  (Early settlers were occasionally astonished to hear pigs squealing in the sky.  They wrongly assumed pigs were literally flying…until they looked up and saw an eagle carrying some farmer’s piglet.) And oftentimes, hunters simply shot eagles (and all birds) for the hell of it.  The bald eagle population had been decimated long before DDT was ever sprayed.  Early American settlers traveling up and down rivers saw eagles almost daily, and natural fish kills attracted dozens of these magnificent birds that came to scavenge.  Now, the only nesting eagle in Floyd County, Georgia is on camera where thousands of people follow its every move.  How sad.

Is it any wonder why I fantasize about living in a wilderness as it existed before people ruined it?  I want to be able to approach an eagle’s nest without some do-gooder fussing at me.  I’d like to see a clear river, unmuddied by erosion, where a superabundance of fish are visible.  I’d like to be able to catch, keep, and actually eat a lake sturgeon without fear that I was dining on the last one in existence.  I hate living in a world where eagles and sturgeon are rare but muddy rivers commonplace.

The Rodent Fossils Found in Kingston Saltpeter Cave

January 19, 2014

When a new Pleistocene-aged fossil site is discovered, the average layman is likely to be most impressed with the fossils of the large extinct species, but scientists are often more excited about finding the remains of the smaller species.  Large mammals usually have wide ranges and can survive in a greater variety of habitats than smaller animals.  It’s hard for scientists to determine the paleoenvironment of a fossil site based on just the bones of larger species, but most smaller species require specific habitat types.  The composition of smaller species helps scientists better understand what the environment was like at the site during the time of fossil deposition. This explains the value of the Kingston Saltpeter Cave site in Bartow County, Georgia where many fossils of small mammals, reptiles and amphibians, birds, and even fishes were found.

Location of Bartow County, Georgia and Kingston.

Photo of the entrance of Kingston Saltpeter Cave.  It’s part of a 40 acre Nature Preserve protected by a private organization.  It’s generally closed to the public due to vandalism.

http://www.youtube.com/watch?v=5Qy93sGu6sg

The above link is a video slideshow of Kingston Saltpeter Cave.

Radiocarbon dating of white tail deer and long-nosed peccary fossils found in the cave produced dates of 12,400 and 12,700 years BP, roughly translating to 15,100 calender years BP.  During this time period, a rapidly warming climate was bringing an end to the Ice Age.  Many species that favor cooler climates still occurred in Georgia then, probably as relic populations.  The environment around Kingston Saltpeter Cave at the time the fossils became deposited has been interpeted as being mostly old growth deciduous forest but with some open woodland, grassland, and wetland nearby. Oak leaves, acorns, hackberry seeds, and charcoal were found in the fossil deposit but were never formally studied.  This is evidence of hardwood forest and forest fires.  I suspect oak trees were beginning to replace the northern species of pine and spruce that predominated here during the Last Glacial Maximum, and forests were expanding at the expense of the more extensive grasslands that occurred during the height of the Ice Age.  However, fossils of prairie chickens and upland sandpipers from this site show that small prairies still existed in the vicinity, and the continued presence of red squirrels suggests jack and white pine, and spruce  trees were still extant.

Kingston Saltpeter Cave served as a roost for at least 3 species of owls, including screech (Otus asio), probably a long-eared (Asio sp?), and a very large unknown extinct species (Strigidae sp?).  See https://markgelbart.wordpress.com/2013/04/22/the-unknown-owl-of-pleistocene-georgia/

Long-eared owl (Otus asio).  This is probably 1 of the at least 3 species of owls that roosted in Kingston Saltpeter Cave during the Pleistocene.  The fossil material found here can not definitively be differentiated from that of the short-eared owl.

The owls preyed upon at least 17 species of rodents (along with cottontail rabbits, other birds, and reptiles), leaving their remains in what eventually became a fossil deposit covered with rock that fell from the ceiling of the cave.  This collection of small mammal remains probably represents most, if not all, the rodent diversity found in north Georgia about 15,000 years ago.  Several of these species no longer occur in the region.  The eastern heather vole (Phenacomys ungava) no longer occurs farther south than Canada, but during the Ice Age, its present day range was completely inundated by glacial ice.  Evidentally, its range shifted far to the south.

Distribution of Phenacomys ungava

Present day range of the eastern heather vole.  This range was uninhabitable glacier during the Ice Age.  It lived as far south as Georgia then but in low population densities.

Eastern heather vole

The heather vole has been found at other fossils sites in the south but always in low numbers.  The modern southern range limit of the red-backed vole (Cletheromys gapperi)  is extreme northeastern Georgia, but it must have been fairly common in the state during the Ice Age.  Fossils of at least 10 individuals were found in the cave, and they’ve also been found at the Little Kettle Creek site in central Georgia.  The southern bog lemming (Synaptomys cooperi) was abundant as far south as Florida during the Ice Age but no longer occurs farther south than the North Carolina mountains.

Southern bog lemming.  Specimens from at least 17 individuals were found in the cave.  It’s not a true lemming.

The prairie vole (Microtus orchrogaster) currently lives just to the northwest of Georgia, but during the Pleistocene it lived in much of the state–specimens from at least 10 individuals were found in the cave.  Today, meadow voles (M. pennsylvanicus) are rare in the southeast and absent from the coastal plain, though a disjunct population occurs in 1 county in central Florida.  However, they were common in the region during the Ice Age–remains of at least 37 individuals were found in the cave, suggesting they were the most common rodent species in the vicinity then.  The reason for this species’ extirpation in the present day south is a mystery.  Studies show it is not adversely effected by the heat.  Cotton rats occupy the same type of habitat, but there seems to be no direct competition between these 2 species.  Pine voles (M. pinetorum) are the most common vole in Georgia today, and they were almost as abundant as meadow voles in the fossil record of the cave.

Owls left evidence of at least 3 northern flying squirrels (Glaucomys sabrinus) in the cave.  This species no longer occurs south of the North Carolina mountains.  However, southern flying squirrels (G. volans) were far more abundant–remains of at least 17 individuals were left by owls.  Although southern flying squirrels may very well have been the most abundant squirrel species in the vicinity then, this isn’t necessarily the case.  Flying squirrels are nocturnal, making them  more vulnerable to owl predation than other species of squirrel.  Their presence is evidence of old growth hardwood forests.  Specimens from at least 3 red squirrels (Tamiascirius hudsonicus) and 2 gray squirrels (Scirius carolinensis) were found in the cave.  The presence of the former indicates relic boreal conifer forests, while the latter indicates dense oak forests.  Eastern chipmunks (Tamias striatus) were represented in the cave as well.

Red squirrels were possibly just as common as gray squirrels in north and maybe even central Georgia during the Ice Age.  They favor boreal conifer forests which were more widespread then.

Leslie Fay, the scientist who identified the rodent fossils found in this cave, was unable to definitively distinguish to a species level mice in the genus Peromyscus.  This genus includes white-footed mice, cotton mice, deer mice, and oldfield mice.  Nevertheless, remains of mice from this genus were abundant in the cave. Owls brought woodrats (Neotoma floridanus) into the cave, but the low numbers of this species suggests they didn’t occupy the cave itself. Fossils of a few larger rodents were also collected from the cave–beaver (Castor canadensis), muskrat (Ondatra zibethicus), and woodchuck (Marmota monax).  A tributary of the Etowah River flows less than a mile from the cave, and the river itself is barely more than a mile away.  This is why aquatic forms are found among the cave fossils.  Perhaps a large mammalian predator dragged the beaver inside.

By comparison, only a few large mammal fossils were discovered in the cave, including those of several individual white tailed deer and long-nosed peccary.  These were likely the most common large ungulates of old growth forests.  One horse leg bone was uncovered as well.  A single jaguar died in the cave.  Perhaps this individual jaguar dragged the deer, peccary, and horse into the cave.  Several black bears may have used the cave for hibernation and died in their sleep, explaining why their fossils accumulated here.  Somehow, a fragmented tooth of an American mastodon washed into the cave–scant evidence of an animal that commonly foraged up and down the Etowah River.  It’s not clear whether the elk bone found in the cave was part of the fossil deposit or of more recent origin.

Reference:

Steed, Joel; and Larry O. Blair

The Late Pleistocene Record of Kingston Saltpeter Cave, Bartow County, Georgia 

Kingston Saltpeter Cave Project 2005

Kestrel and Cotton Rat

January 16, 2014

I was stuck on traffic-jammed Bobby Jones Expressway in Martinez, Georgia the first time I ever saw a kestrel.  The brave feathered beauty nailed a cotton rat in the grassy median just yards from passing cars.  It’s quite amazing to witness predator-prey interaction in the middle of urban civilization.  I have since seen these diminutive falcons on several occasions, and they always appear to be hunting cotton rats on grassy roadside rights of ways.  Most people don’t realize  there is a healthy population of cotton rats in Georgia, living in the grassy areas along roadside ditches.

Male kestrel.  They’re much more colorful than the females.

Note how small a full grown kestrel is.  While perched on a telephone wire, they could easily be mistaken for a songbird.

Female kestrel.

Kestrels are so small, it’s possible I’d seen them long before my encounter on Bobby Jones Expressway, but perhaps just never noticed them.  They mostly hunt large insects, especially grasshoppers and dragonflies, and small mammals, but they also take lizards, snakes, frogs, and birds ranging in size from humming birds to mourning doves.  Cotton rats are rather small rats, but kestrels will prey upon larger non-native Norway rats and also weasels.  Kestrels often ambush bats exiting caves.  Excess meat is stored in clumps of grass where the falcons will return to feed.  The preferred habitat of the kestrel is forest edge that gives them access to hollow snags for nesting and grassy fields for hunting.

The American kestrel (Falco sparverius) is closely related to the common kestrel (Falco tinnunculus) of Eurasia, and genetic evidence suggests the 2 species diverged during the late Miocene from a common ancestor.  Pleistocene-aged fossils of American kestrels are fairly common, including one specimen found in Kingston Saltpeter Cave in Bartow County, Georgia.

Audubon kept a young kestrel as a pet after he found it had fallen from its nest.  He successfully reared it, and the bird learned to hunt on its own.  This led to its downfall.  Nero (the name Audubon bestowed upon the falcon) made the mistake of attacking some newly hatched chicks.  The mother hen rushed to their defense and pecked the little kestrel to death.

Cotton rat (Sigmodon hispidus).  Quite common in the southeast.

Cotton rats favor early successional habitat–grassy clearings and overgrown fields, thus explaining why they’re found on roadside rights of ways.  Highway maintenence workers keep highway medians in a permanent state of early successional habitat by frequently mowing the grass.  Cotton rats eat green vegetation, especially stems, leaves, and seeds.  They also consume insects and probably quail eggs.  They breed rapidly: gestation is just 27 days, and the females come into heat immediately after giving birth.  This rapid rate of reproduction explains how their populations can explode and provide food for a plethora of predators.

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Photo I took of a naive young cotton rat at the St. Mark’s Wildlife Refuge in Florida last June.  It was not afraid of me at all.

Cotton rats are very common in the Pleistocene fossil record, and their ancestors likely originated in South America.

James Balog’s Misleading Climate Change Lectures

January 12, 2014

Scientists have no way of determining whether changes in recent climate are due to natural variability or man made influences.  Any scientist who claims there is a way to discern this difference is a liar.  To determine man made influences on worldwide climate would require a control earth where man never evolved.    Scientists could then compare the climate of the control earth with that of the earth we live upon.  But there is no control earth.  Instead, scientists are dependent upon mathematical models that calculate natural forcing vs. anthropogenic influences– in other words…wild guessing.

James Balog is a photographer who instigated the Extreme Ice Survey (EIS), a project that has been documenting 16 shrinking glaciers with 33 cameras since 2007.  He has completed a documentary for National Geographic, and he’s frequently on the lecture circuit.  One such lecture can be seen on youtube. http://www.youtube.com/watch?v=DjeIpjhAqsM  The EIS is a worthwhile project, however, his lectures are alarmist and misleading.  He admits to formerly being skeptical about anthropogenic influences on global warming, acknowledging, as I do, that it is based on mathematical models.  But when he started seeing physical evidence of glaciers receding, he became a believer.  I find this leap of faith deceptive.  True, 95% of earth’s glaciers are receding, but this is not evidence that humans are responsible.  Natural cyclical warming may be causing the glaciers to contract.

During his lectures, Mr. Balog shows a map of the Ilulisset Glacier in Greenland and how it has receded since 1850.  This is extremely misleading.  A cool period, known as The Little Ice Age, ended in 1850.  This cool climate phase began about 1300, and the Ilulisset Glacier expanded for 550 years.  Its recent reduction may be due to natural variability as the climate has rebounded since the end of The Little Ice Age.  I’d like to ask Mr. Balog why he doesn’t show a map of the Ilulisset Glacier since 1100 or 1300.  Why start at 1850? I accuse him of being purposefully misleading.

Global warming alarmists like to claim the recent spike in global temperatures is unprecedented.  A glance at the geological record of past average worldwide temperatures debunks this ridiculous claim

Graph of average annual temperatures over the last 1000 years from glacial ice core data.  Present annual average temperatures are now approaching those of the Medieval Warming Period but are still about 3 degrees Fahrenheit less.

A graph of the last 15,000 years shows average annual temperatures are lower today than they’ve been throughout much of the last 10,000 years, and the recent rise is nowhere close to being unprecedented.

15,000 years ago, annual average temperatures rose 21 degrees Fahrenheit within less than a century, far surpassing the 1 degree rise of the last century.  This is known as the Boling-Alerod warm phase and it brought the last Ice Age to an end.  A sudden 14 degree F drop in temperatures 12,900 years ago precipitated the Younger Dryas cold phase.  This phase ended just as abruptly 11,500 years ago with another 21 degree F rise.  All of these climatic fluctuations occurred well before man was releasing any significant quantities of greenhouse gases.  Modern day temperatures are still 3 degrees F less than the warmest phase of the Medieval Warming Period, a phase of climate that lasted from 900 AD to 1300 AD.  (Scientists dispute whether this phase of climate was restricted to northern Europe or was a worldwide phenomenon.  More data is probably required.)

A new study led by Buffalo University scientist Jason Briner discovered that the Jakobshiva Isbrae Glacier in Greenland expanded during the Little Ice Age as rapidly as it is currently receding.  The disintegration and re-expansion of glaciers is a natural occurrence and nothing to be alarmed about.  Calling it unprecedented is simply a lie.

Map showing the reduction of the Jakobshiva Isbrae Glacier in Greenland.  A new study found it expanded as rapidly during the Little Ice Age as it is now shrinking.

I think people should work to reduce greenhouse gas emissions as much as possible because we shouldn’t treat earth’s atmosphere like a giant chemistry experiment.  But I doubt humans will ever take serious action.  Few people are willing to give up electrical power generation or automobiles.  Fossil fuels are finite, though, and some day the human race will run short of carbon-based energy sources, thus haulting the emissions of greenhouse gases into the atmosphere.  One way or another it will come to an end.

New Species of Early Pliocene Saber-tooth (Rhizosmilodon fiteae) Discovered in Florida

January 8, 2014

Phosphate mining requires the removal of 50 feet of soil, resulting in severe environmental degradation.  By law, mining companies must restore the land following completion of mineral extraction, but it will be centuries before anyone can honestly say the eyesore has been returned to a pristine condition.  Strip mining operations are bad for the environment, but they often expose fossiliferous strata, much to the delight of paleontologists.  Fossil hunters prospecting the spoil piles of the Fort Meade phosphate mine in Polk County, Florida found the remains of 70 species of vertebrates (from thousands of specimens)  dating to the early Pliocene (~4-5 million years BP).

Map of Florida highlighting Polk County

Polk County, Florida–the location of the Fort Meade Mine where many early Pliocene fossils were found.

Fort Meade Mine in Florida.  Scientists discovered an early Pliocene fauna of fossils here in the excavated spoil piles.  

Periodic sea level transgressions explain why marine fossils were found mixed with fossils of land mammals at this site.  Shark’s teeth, including those of the extinct Hemipristis, along with gar and barracuda remains, turtle shells, and fossils of alligators, seals, and whales were found next to the bones of many species of mammals known to have lived in North America during the early Pliocene, just before Ice Ages began occurring.  This was the final age of the hippo-like rhino (Teleoceras), a beast that was about to become extinct after being the most common large mammal here for millions of years.  Several species of 3-toed horses, as well as long-necked camels and llamas browsed the subtropical vegetation.  Eocoileus, the earliest known ancestor to the modern white tail deer and probably the first deer species to live in North America, was part of the fauna then.  Two elephant-like animals–a gompothere and Matthew’s Mastodon–trudged through the forests.  There were 2 types of short-faced bears, a flat-headed peccary, a ground sloth, and a bobcat (Lynx rexroadensis) that were all probable ancestors to the more recent and better known Pleistocene forms.  However, it was the last stand for the extinct bone-eating dog (Borophagus).  This carnivore left no descendents.  Altogether, this list of species is known as the Whidden Creek Local Fauna which corresponds to the regional Palmetto Fauna.

Perhaps the most interesting fossils from the Whidden Creek Local Fauna were the 2 species of saber-tooth cat.  Machairodus colorodensis was a lion-sized saber-tooth that may have been top predator here then.  Scientists at first misidentified the smaller jaguar-sized saber-tooth.  All they found was 1 jaw and based on that specimen it was thought to belong to a Megantereon hesperus, a species known to have ranged well to the north and west of Florida.  However, scientists later found a few more jaws and leg bones assumed to originate from the same species.  Based on this material, they determined the fossils were from a previously unknown species.  They named this new species Rhizosmilodon fiteae.  They believe this new species was ancestral the the early Pleistocene species Smilodon gracilis which was in turn ancestral to 2 late Pleistocene species–Smilodon fatalis and Smilodon populator. The former ranged across North America, while the latter lived in South America.

Figure 1 Examples of the Palmeto Fauna machairodont.

Jaw and leg bones of Rhizosmilodon fiteae–a probable ancestor to Pleistocene species of Smilodon.

There are several anatomical characteristics that differentiate Rhizosmilodon from its later descendents: It has more minor serrations on its canines, a less developed mandibular flange, larger lower canines, and a lower premolar that is absent or reduced in Pleistocene species of Smilodons.  The mandibular flange is the recess in the lower jaw that acted as a space for the large upper canines when the jaw was shut.

The scientists who identified Rhizosmilodon believe it is a related sister species to Megantereon hesperusRhizosmilodon and Megantereon likely co-occurred temporally but in different geographical ranges.  Rhizosmilodon’s ancestors spread throughout North America, while Megantereon’s ancestors dispersed to Asia, Europe, and Africa.  Rhizosmilodon is the oldest known ancestor to Smilodon and suggests a North American origin of the genus.

Refererence:

Wallace, Steven; and Richard Hulbert

“A New Machairodont from the Palmetto Fauna (Early Pliocene) of Florida, with comments on the origin of the Smilodontii (Mammalia, Carnivora, Felidae)

Plos One March 2013

http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0056173

The Animal Finders Guide

January 2, 2014

Dogs and cats make the best pets.  Both species have evolved to live with people, and evidence suggests they adopted us rather than vice-versa.  Dogs (Canis familiaris) evolved from wolves (Canis lupus) that hung around hunter-gatherers to feed upon the camp’s discarded meat refuse.  Cats (Felis cattus) evolved from Eurasian wildcats (Felis sylvestri) that hunted small rodents attracted to agricultural people’s stores of grain.  The close proximity between humans and cats and dogs over thousands of years has strengthened the traits that make them such fine companions.  The same is not true for exotic wild animals, yet many people like to keep these potentially dangerous and unpredictable animals as pets.  They should stick with dogs and cats.

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December issue of The Animal Finders Guide, a publication for exotic animal breeders looking to sell or buy.

The Animal Finders Guide is a kind of want ad publication used by people looking to buy or sell exotic animals.  Many states have minimal or no laws regulating this trade.  I recently purchased a copy of this publication because I was curious what kinds of exotic animals are available.  Some of these breeders are willing to ship their animals in a crate, while others won’t deal the animal unless they meet the buyer in person and are assured they are equipped to handle it.  This demonstrates the varying degree of care people have for their animals.  Some of the species  listed for sale in the publication aren’t particularly exotic–camels, obscure breeds of cattle, reindeer, and swans.  Camels seem to be especially popular.  They’ve been domesticated for thousands of years, so I think they might make good pets for people who live in the country.

White double humped Bactrian camel.  This variety seems to be a big deal for camel breeders.

However, I think some people must be out of their minds to want to raise some of the other species for sale.  African crested porcupines sell for $1500.  The spines must be a hazard when handling.  A sloth costs $2000.  Peccaries can be had for $300.  Someone is selling an adult baboon for $300.

Who in their right mind would want to own a baboon?  They have bigger fangs than a dog, plus a dog can just bite…a baboon can grab and bite, so that the victim can’t even pull away.  If you are crazy, you can buy one for $300.

Pet marmoset–a much safer choice of primate than a baboon.  They sell for at least $1500.

Bottle fed zebras go for $5000.  Unlike horses, zebras can not be tamed enough to ride.  A red kangaroo just out of the pouch costs $1500.  A coati-mundi is only $150.

Bottle feeding a baby kangaroo.  Looks cute now, but an adult kangaroo can disembowel a man with a single kick to the gut.

In the particular December issue I purchased, there were no ads for sellers of big cats, but there was a listing for a buyer seeking cougar kittens.  I just can’t understand why anyone would want to keep a cat that could snap his neck or bite through his windpipe.

The December issue of The Animal Finders Guide has a number of interesting articles about rearing exotic animals.  Perhaps the most interesting was one about raising elk which can be raised like beef cattle for meat.  There was also an arch conservative editorial entitled “If the Cities Burn.”  In this editorial Pat Hoctor, the publisher of the Animal Finders Guide, denounces the liberal media, the Supreme Court, and modern schools that supposedly, according to Mr. Hoctor, don’t teach reading, writing, and history. (I know this is bullshit–my daughter just made it through a public school system and she was definitely taught all 3 of these subjects.)  He finished his rant by claiming newspapers are full of lies (I wonder where he gets his news) and how city dwellers are misled and uneducated.  Wow!  He sounds like a lonely bitter old man who hates city slickers.  Maybe he should cheer up and try to find a date on Farmersonly.com.