Extralimital Species of Pleistocene-aged Turtle Remains Found in the Upper Coastal Plain of Alabama

George Phillips wrote his Masters Thesis about Pleistocene-aged, non-mammalian, vertebrate remains found in creeks that flow through the Alabama and Mississippi upper coastal plain, a region also known as the Black Prairie.  Turtle shells are by far the most abundant remains found here because of preservational bias.  Turtle shells are very durable, helping protect the reptile while they are alive.  This durability also makes turtle shells more likely to survive the ravages of time when the bones of most other vertebrates disintegrate.  The results of his study show that several species of turtles have experienced interesting range redistributions since the end of the Ice Age.

Dallas County, Alabama.  Bogue Chitto Creek, located in this county, yields many Pleistocene fossil remains.

Blanding’s turtle (Emboidia blandingii) is an endangered species presently restricted to the upper Midwest and parts of New England.  Most of this species’ present day range was under glacial ice during the Ice Age and thus uninhabitable.  Remains of Blanding’s turtle can be found in Pleistocene deposits as far south as the Black Prairie region in Alabama.  The presence of this species in Alabama suggests much cooler summers in the south during the Ice Age (though winters may have been as mild or just a little cooler than those of today). Blanding’s turtles may be unable to endure the long hot summers of the present day south, and this may be the limiting factor on their range today.

Blanding’s Turtle occurred in Alabama during the Ice Age but no longer ranges this far south.

Present day range of Blanding’s turtle.  During the Ice Age about 70% of this territory was under glacial ice.

The wood turtle (Glyptemys insculpta) is another species of turtle with northern affinities that lived in Alabama (and other parts of the south) during the Ice Age.  This species may also be unable to survive long hot summers.

Wood turtle.

Present day range map of the wood turtle.  During the Ice Age >90% of this range was under glacial ice and this species retreated south.  Longer hotter summers chased them back up north.

The only known Pleistocene-aged specimen of a musk turtle (Sternotherus carianitus) was found in Catalpa Creek, Alabama. Today, this species occurs to the west of this site.  Its rarity in the fossil record is unexplained and is probably just due to chance.  During the Pleistocene it apparently ranged further east than it does today.  Any number of unknown reasons could explain its extirpation from the most eastern parts of its range–disease, excessive egg predation, or competition with other species of turtles.

Musk turtle.

Present day range map for musk turtle.  They formerly ranged a little further east during the Pleistocene.

There are 3 species of red-bellied turtles.  The Florida red-bellied turtle (Pseudemys concinna) is presently restricted to peninsular Florida, but Pleistocene-aged remains of this species have been found in Bartow County located in north Georgia.  The Alabama red bellied turtle (Pseudemys alabamensis) is presently restricted to extreme southern Alabama and Mississippi.  The red bellied turtle (P. rubriventris) is presently restricted to the mid-Atlantic states, but Pleistocene -aged remains of this species have been found in the upper coastal plain of Alabama.  It’s likely these 3 species of red-bellied turtles diverged from 1 continuous population that existed before the Pleistocene-Holocene transition when for some unknown reason they became geographically isolated into their present day ranges.  Their curious range distributions beg for a study of their molecular DNA.  The 3 present day species represent a speciation event that may have occurred as recently as 10,000 years ago.  I can’t determine why red-bellied turtles were extirpated from regions in between their present day ranges.  Did overharvesting by humans play a role?

Present day range map for the mid-Atlantic red-bellied turtle (Pseudemys rubriventris)  Remains of this species have been identified from Alabama.

Range map for Alabama red-bellied turtle.  The Pleistocene/Holocene transition was likely a speciation event that caused the 3 species of red-bellied turtles to diverge.

An extinct Pleistocene subspecies of box turtle (Terapene Carolina putnami) was common in Alabama’s coastal plain.  It was larger than present day box turtles but otherwise was similar.  There is no direct evidence of gopher tortoises (Gopherus polyphemus) from the Black Prairie region during the Pleistocene, but a Pleistocene-aged specimen of an indigo snake was found in Bogue Chitto Creek located about 40 miles north of the present day range of this tortoise.  Indigo snakes depend upon gopher tortoise burrows for shelter, so the presence of this snake suggests the presence of gopher tortoises nearby.  Gopher tortoises require sandy soils for burrowing.  They don’t burrow in the heavy upland clay soils so widespread in this region, but they may have burrowed in the alluvial (streamside) sands by the creek.  Gopher tortoises require open environments where they can feed upon short sun-loving plants.  The closure of the forest canopy would have caused their extirpation here.

Two scutes of the extinct giant tortoise (Hesperotestudo crassicutata) were found in this region.  Scientists puzzle over the co-existence here of the cold adapted wood turtle and Blanding’s turtle with the giant tortoise, a species they assume required a frost free environment.  I disagree with their assumption.  I hypothesize giant tortoises were capable of surviving freezing temperatures by either burrowing underground, like their closest living relative (the gopher tortoise), or by utilizing burrows dug by giant ground sloths. If giant tortoises could survive mild frosts as I believe, this species could have co-existed in the same region as cold-adapted species of turtles.  However, it’s just as likely their remains represent a warm climate phase, temporally distinct from when wood turtles and Blanding’s turtles roamed the creek bottoms.  As far as I know, none of these specimens has been radio-carbon dated.

Species of turtle remains found in Pleistocene deposits here that still occur in the region include snapping turtle, alligator snapping turtle, spiny softshell, stinkpot, painted, slider, and Alabama map turtles.

Reference:

Phillips, George

“Paleofaunistics of Non-mammalian Vertebrates from the Late Pleistocene of the Mississippi Black Prairie”

North Carolina State Masters Thesis 2006

If I could live in the Pleistocene part XI–The Turtle trap and my Pleistocene Pot Party and Playlist

In this irregular series “If I could live in the Pleistocene…,” I imagine what my life would be like, if I could travel back in time to ~39,000 BP and live in the geographical area later to be known as central Georgia but with some selected modern conveniences I brought  with me.  I constructed an adobe home that is sort of like a mini-castle with a watchtower and a high stone fence surrounding a farm where I raise and grow most of my own food.  I generate my own electricity and even have wires going through the time tunnel so I can communicate with the modern world.  I enjoy an idyllic life of farming, hunting, and fishing in a pristine wilderness that exists before man ever colonized the region.  I located my home about a mile north of the Broad River for ready access to fish and aquatic animals.  On previous segments of this series I’ve discussed fish traps and turkey traps.  Today, I’ll show how I catch turtles and discuss the species usually found in my traps.

My last adventure (https://markgelbart.wordpress.com/2012/11/02/if-i-could-live-in-the-pleistocene-part-x-turning-a-bear-into-soap/) in November was the dilemma I faced when I ran out of soap and my concubines wouldn’t sleep with me until I made a new supply.  I ended up having to kill a big old bear  in order to get enough animal fat to make soap.  We spent the winter eating hamburgers made out of a blend of bear meat and venison.  Water levels were too high for fish and turtle trapping, but spring is here and the river level dropped.  We’re ready for a change in our diet.  The fish trap provides more food than we can eat, but we want something different.  Fortunately, catching turtles is just as easy as catching fish.  I simply constructed a small cage made out of chicken wire and attached 2 styrofoam floats to it.  The cage has no top.  Instead, a piece of wood is placed on 1 side and suspended over  the cage. A spring holds the piece of wood over the top. When a turtle crawls on the wood over the cage, its weight causes the wood to teeter, and the turtle falls into the cage.  The spring snaps the wood back in place, ready for the next turtle.

Illustration of a turtle trap.  The turtle crawls on the suspended wood to sun itself.  The wood acts like a teeter-totter and drops the turtle into the trap.  A spring snaps the wood back into place.  I place my trap in a shallow part of the river and anchor it down.

The most common kind of turtle found in my trap is the river cooter (Pseudemys concinna).  It’s also known as the chicken cooter because it affords about as much meat as a chicken.  It was a common source of protein for slaves on southern plantations before the Civil War.  Chicken cooters are omnivorous but mainly feed upon aquatic vegetation.  During winter they burrow into mud at the bottom of a water course and literally breathe through their ass–their cloaca can absorb oxygen from the water.  In real life chicken cooters are still abundant, especially in suburban ponds where humans have forgotten they are good to eat.

River or chicken cooter.

I also catch Florida red-bellied turtles (Pseudemys nelsoni).  Florida red-bellied turtles have an interesting distribution history.  Today, this species is restricted to Florida and extreme southeastern Georgia.  (An introduced population thrives on the San Marcos, River in Texas.)  However, fossils of this species were found at the Ladds site in Bartow County, Georgia about an hour north of Atlanta.  The Ladds site likely represents the Sangamonian Interglacial interval.  Florida red-bellied turtles were once more widespread through the south.  Moreover, there are also 2 geographically distinct but closely related species of red-bellied turtles–P. rubriventis of the mid-Atlantic states and P. alabamensis of southern Alabama and Mississippi.  Red-bellied turtles prefer ponds and still waters rather than rivers.  This habitat preference may explain why there are no red-bellied turtles living within a range they used to inhabit.  Red-bellied turtles must have difficulty dispersing following environmental changes that result from climate perturbations.  Arid climate during the Last Glacial Maximum reduced available aquatic habitat, and red-bellied turtles have since failed to reoccupy much of their former range.

Florida red-bellied turtle.

Range map of Florida red-bellied turtle.  Before the LGM they had a broader range across the south.  They have so far failed to recolonize their former range since the Ice Age.

Soft-shelled turtles (Apalone spinifera) fall into my trap.  This large predatory species is just as aggressive as a snapping turtle, and they have a longer neck, so I have to be careful when handling them.  They feed upon fish, frogs, and ducks. They are surprisingly fast.  In real life I once saw a soft-shelled turtle running down a hillside, and it demonstrated blazing speed–I think faster than a rabbit.  So much for the tortoise and the hare myth.

Soft-shelled turtle. They grow to 40 pounds.

Snapping turtles (Chelydra serpentina) weigh up to 35 pounds, and when I catch 1 of these, I have extra meat for my freezer.

Snapping turtle feeding on a bream.

Turtle meat tastes like lobster.  In real life I found turtle meat for sale at a Kroger supermarket seafood department.  It was imported from New Zealand.  (Americans can’t even raise their own turtles?)  I made a delicious catfish and turtle stew.

Turtle and catfish stew.  Has potatoes to make it substantial.  Seasoned with chili powder, bacon, and onion.  Delicious.

I’m not going to go into all the gruesome details of killing and butchering the turtles I caught.  I put some into a tank to be fed a special clean diet until we’re ready to eat them, but I did kill and clean a medium-sized snapper.  It’s important to wash hands when handling turtles because they carry salmonella just like chickens.  Some turtles provide a bonus–unlaid eggs.  Turtle eggs are good for cooking and make for rich cookies and cakes, but they have an unusual property.  The whites of turtle eggs never get hard, no matter how long they are boiled.  The white remains liquid around the hard yolk.

While my turtle stew is slow-cooking on the stove, I decided to get high and listen to music before supper.  I carried a big stein of home-made beer (made with barley and hops I grew) and a joint of my  marijuana (which I also grew on my Pleistocene farm) to the top of my 5-story castle watchtower, constructed in the shape of a lighthouse, where I can observe the wilderness surrounding my home.  This is my favorite kind of party: listening to music undisturbed by anybody–even my concubines leave me alone and stay downstairs.  I flip on the tunes, enjoy the scenery, and get wasted.  If I went back in time, I’d have to bring rock and roll music with me.  Here’s my Pleistocene playlist.  (Realize this: I play these songs in exact order while I keep getting more and more wasted.)

“Oh Carol” — Chuck Berry showing Keith Richards how to play the song.http://www.youtube.com/watch?v=PEA6gzAAPfc

“Can’t you hear me knocking”–Rolling Stones

“It’s only Rock and Roll”–Rolling Stones

“Got to get you into my life”–Beatles

“Yer Blues”–Beatles

“I am the Walrus”–Beatles

“You gotta fight for your right to Party”–Beastie Boys

“Low”–Cracker

“Longview”–Green Day

“Brain Stew”–Green Day

“Delivering the Goods”–Judas Priest

“Devil’s Child”–Judas Priest

“Living after Midnight”–Judas Priest

“Falling in Love”–Scorpions

“Loving you Sunday Morning”–Scorpions

“Animal Magnetism”–Scorpions

“Chained”–Van Halen

“Hot for Teacher”–Van Halen

“Heavy Metal”–Sammy Hagar

“Flying High Again”–Ozzy Osbourne

“No More Tears”–Ozzy Osbourne

“Sweet Leaf”–Black Sabbath

“Fairies Wear Boots”–Black Sabbath

“Still Raining, Still Dreaming”–Jimi Hendrix

“Freedom”–Jimi Hendrix

“Ezy Ryder”–Jimi Hendrix

“How Many More Times”–Led Zeppelin

“The Lemon Song”–Led Zeppelin

“Rock and Roll”–Led Zeppelin

“Over the Hills and Far Away”–Led Zeppelin

“Custard Pie”–Led Zeppelin

“For your Life”–Led Zeppelin

“I Can’t Quit You”–Dred Zeppelin

“Oh Darling”–Beatles

“Big Love”–Robert Plant

“Radioactive”–The Firm

“Social Disease”–Elton John

“Dan Dare: Pilot of the Future”–Elton John

“Funeral For a Friend/Love Lies Bleeding”–Elton John

“Spanish Flea”–Herb Albert

“Rise” –Herb Albert

“Can’t Keep My Eyes off of You”–Frankie Valli

Sex cures hangovers.  Excessive alcohol consumption causes an imbalance of dopamine levels in the brain.  Having sex helps restore dopamine levels.  My concubines, the Jenna Shea and September Carrino lookalikes, are going to help restore my dopamine levels following my Pleistocene beer and pot party.