Archive for September, 2012

How Recently did the Jaguar (Panthera onca) Roam Eastern North America?

September 26, 2012

Most people think of the jaguar as a tropical species of cat that lives in deep jungles.  But human persecution is the reason the majority of the world’s remaining population of jaguars lives in remote jungles.  Jaguars can only survive in areas where human density is low.   Ranchers defending their livestock, and people coveting the big cat’s beautiful spotted coat eliminate jaguars from many areas far outside tropical jungles.  The jaguar is probably as adaptable as the Asiatic tiger which ranges into temperate and even boreal forests.  Today, jaguars are known to occur in the deserts of northwest Mexico.  If they can live in jungles and deserts, surely they could adapt to temperate forests as long as suitable prey was available. The Pleistocene fossil record proves that jaguars once ranged over most of North America.  Jaguar fossils have been found as far northwest as Whitman County, Washington and as far northeast as Port Kennedy, Pennsylvania.  Across the southeast jaguar fossils are among the most common of the large carnivores found by fossil collectors.  Along with dire wolves they were probably a dominant predator in the region’s forests for most of the Pleistocene, being more common than the infamous saber-tooth.  So how recently did this dominant predator of the Pleistocene roam North America east of the Mississippi?

Historical range of the jaguar shaded red.  A jaguar was possibly killed 1o miles east of the Mississippi River in 1886. John Lawson wrote that he saw a “tyger” in North Carolina circa 1710.  He knew the difference between a cougar and a jaguar, so I doubt he was mistaken.  The Pleistocene range of the jaguar extended as far north as Washington state and Pennsylvania.  I suspect its Holocene range was also greater than range maps indicate.

I believe Indians gradually overhunted most of the megafauna to extinction between 15,000 BP-~7,000 BP, completely eliminating some species from some regions but haphazardly leaving remnant populations in inadvertent refuges until those too were wiped out.  Jaguars on average take larger prey than cougars, so the decline in megafauna diversity reduced jaguar populations across much of their former range.  Moreover, the Indians directly hunted jaguars for their spotted coat, further reducing their numbers.  Still, there is no ecological reason why jaguars couldn’t have persisted in eastern, particularly southeastern, forests, as long as there was plenty of deer.  In the mid-1960’s a jaguar escaped from captivity and lived in a Florida marsh near Vero Beach for 2 years until a hunter killed the cat.  And deer populations were smaller then than they are today.  Jaguars must have been largely absent from pre-settlement eastern forests because the pre-Columbian population density of Indians was just too high.  However, male jaguars sometimes roam for up to 500 miles.  There was enough wilderness left that a jaguar occasionally could range undetected into the managed woodlands adjacent to Indian towns.  (Indians set fire to the forests regularly to improve habitat for game.) Several artifacts do show that eastern and midwestern Indians did know what jaguars were.

A gorget made out of a conch shell with a jaguar engraving.  This was found in Missouri.

Posted Image

Jaguar paw prints in a Missouri Cave.  Their age is unknown.

The Missouri conch shell gorget undoubtedly represents a jaguar.  The conch shell, imported from the coast, suggests Indian trade routes from Benton County, Missouri to the sea but, of course, is not proof jaguars lived in Missouri during the time period.  Engraved images of jaguars on 2 bones excavated from a Hopewell burial mound in Ohio date to about 500 AD.  One of the bones was of a human.  They could have been engraved by a person from west of the Mississippi, but perhaps jaguars occasionally wandered into Ohio then.  Two Indian artifacts from Moundsville, Alabama–an effigy pipe and a shell gorget–represent jaguars.  Pottery dating to between 1100 AD-1700 AD found in Florida is engraved with images of a cat.  The engraving is perforated.  The perforations may represent spots, but may also be a design that prevented the pottery from shattering when heated.

John Lawson, an early naturalist explorer (See https://markgelbart.wordpress.com/2012/07/27/john-lawsons-voyage-to-carolina-1700-1711/ ), did write that he saw a “tyger” once.  He never went west of North Carolina, and he knew the difference between a cougar and a jaguar, so I regard this as probable evidence of a jaguar in North Carolina between 1700-1711.  They were rare but present.  Here’s his account:

“Tygers are never met withal in the Settlement; but are more to the Westward, and are not numerous on this Side the Chain of Mountains.  I once saw one, that was larger than a Panther and seem’d to be a very bold Creature.  The Indians that hunt in those Quarters, say, they are seldom met withal.  It seems to differe from the Tyger of Asia and Africa.”

A newspaper article from a June 1886 edition of the Donaldsonville Chief, may be the most recent documented proof of a jaguar east of the Mississippi River.  A big cat had been killing cattle in Ascension Parish, Louisiana which is 10 miles east of the Mississippi River.  Allen Martin and Johnny Walker tracked the big cat down and sicked their dogs on it.  The cat killed 3 of the dogs before one of the hunters “laid it low” with a rifle shot.  They reported that it was 8 feet long and weighed 250 pounds, and they referred to it as an “American tiger,” not a panther.  They were familiar with panthers.  This cat was significantly larger than a panther, or cougar.  The name American tiger was formerly used for jaguar.  Though this probably is an account of a jaguar, curiously there’s no mention of a spotted coat, so it’s not 100% certain.  If it is, this means jaguars persisted in Louisiana 26 years later than those in California which were eliminated there by 1860.  Jaguars continued to range the big thicket region of eastern Texas until about 1902.  An average of 1 was killed annually in south Texas, Arizona, and New Mexico until 1948 when a predator control poisoning program on both sides of the U.S./Mexican border caused their complete extirpation north of the Rio Grande along with Mexican grizzlies and wolves.  Within the last decade jaguars have occasionally ranged into New Mexico, but the xenophobic fence built to keep Mexicans from crossing the border will hinder the jaguar’s return as well.

References:

Daggett, Pierre; and Dale Henry

“The Jaguar in North America”

American Antiquity 39 (3) July 1974

Nowak, Ronald

“A Possible Occurrence of the Jaguar in Louisiana”

The Southwestern Naturalist 17 (4) 1973

See also: https://markgelbart.wordpress.com/2010/07/08/cougars-vs-jaguars/

Jaguar killing a caiman.

Port Kennedy Cave, Pennsylvania

In 1871 workers excavated stone from a limestone fissure they named Port Kennedy Cave, later known as bone cave for all the bones they found.  This cave in near the historic Valley Forge, Pennsylvania.  Cope was the first scientist to identify the fossils found here, but over the past centuries dozens of scientists have studied the specimens because it’s an important Irvingtonian-aged site.  Based on the species of fossils, they’re estimated to be between 1.5 million-300,000 years old which is the Irvingonian Land Mammal Age.  The list of species found here includes Wheatley’s ground sloth, evolutionary ancestor to Jefferson’s ground sloth; Smilodon gracilis which is ancestral to Smilodon fatalis ; the lesser short-faced bear (Arctodus pristinus) ancestral to the giant short-faced bear (Arctodus simus); black bear (Ursus americanus), tapir, peccary, wolverine, skunk, and mastodon.  There were a lot of fossils of smaller animals too, but the excavation at this early date was so clumsy they disintegrated into useless fragments.  Later, groundwater flooded the site, ending the collection of fossils here.  Ehret Magnesium Company dumped asbestos and other debris on the fissure and now it’s buried and lost.  I haven’t been able to determined from information on the web whether recent attempts to relocate the site have been successful.

I mention this site because it’s the northeasternmost known pre-historic occurrence of the jaguar.  Fragmentary remains of a probable jaguar were found in Washington State, making that the northwesternmost locality known of a pre-historic jaguar, but a complete jaguar skeleton dating to 38,600 BP was found in an Oregon cave where a 50,000 year old grizzly skeleton was also found.  That is the oldest grizzly bear fossil known in North America.

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The Bobcat (Lynx rufus)–Another Pleistocene Survivor

September 20, 2012

On New Year’s Day 2005 I saw a live wild bobcat.  This is the only time I’ve ever seen one.  I was looking out the window and noticed the brown rump of what I thought was a medium-sized dog.  It had a bob-tail and was sniffing around my neighbor’s mailbox.  I realized it was a bobcat, not a dog, and I rushed outside to take a closer look.  By this time it had wandered into the vacant lot across the street from my house.  I tried whistling to see if I could get it to approach me.  Instead, it stared at me, and its eyes widened in fear, as if it had never seen a human before.  The cat retreated in zig-zag pattern into the brush that then covered the lot.  This bobcat was much longer and larger than an ordinary housecat.  Though the rump was brown with black spots, most of its body was tawny-colored, so that it could blend with winter shades of grass.  Perhaps not coincidentally, a few months earlier a bobcat killed a 120 pound pit bull terrier on Beech Island, South Carolina about 20 miles from my house.

2004 article from The Augusta Chronicle detailing the fatal attack of a bobcat on a 120 pound pit bull terrier in Beech Island, South Carolina. Click on the image to make the article large enough to read.

According to the dog-owner, she heard her dogs making a commotion.  She went outside and tried to drive the cat off with a stick, but the cat chased her back inside her trailer.  I believe it may not have been coincidence that I saw one within the same year because bobcat populations are cyclical. The local bobcat population may have been high following a cyclical increase in the rabbit population, though they’re not supposed to be as tied to cottontails as their cousins, the Canadian lynx, are to snowshoe hares.

I think bobcats are rather uncommon most of the time in the region where I live.  Road-killed deer and coyotes are common, but I’ve never seen a road-killed bobcat.  I may be wrong, however; bobcats may simply avoid roads whereas coyotes hang around roads to scavenge the automobile carnage, explaining why they’re more often hit by cars.  Radio telemetry studies do show that bobcats avoid roads.  A healthy population of 26-35 bobcats living on Kiawah Island, South Carolina (near Charleston) has been intensively studied.  Scientists have come across a few road-killed bobcats there.  Kiawah Island bobcats help keep the deer population in check, and they are welcomed by nature-loving residents.  One study mentions a well-meaning but misguided tourist who chased away a bobcat that was about to kill a deer fawn on a golf course.  Do-gooders like that just get on my nerves.

This robust looking bobcat killed this mule deer.

Rabbits and rodents make up the majority of a bobcat’s diet.

This bobcat conquered a snake.

Bobcats were introduced to Cumberland Island, Georgia in 1989 in the hopes they would help control the feral hog population by abducting the piglets.  Bobcats were extirpated from the island circa 1910.  They adapted well to this roadless environment which consists of beach, interdune myrtle thickets, maritime live oak and pine forests, palmetto scrub, and fresh and saltwater marshes.  Wilderness areas on the southeastern coastal plain may host up to about 3 bobcats per 5 square miles.  Developed areas support a smaller density of bobcats because they are forced to roam wider areas in order to avoid people.  Their diet includes approximately 20% deer, 65% rabbits and rodents (especially cotton rats), and the balance consists of birds, reptiles, and insects.

Adult bobcats weigh between 20-50 pounds.  It’s surprising that a 20 pound cat can kill a 200 pound deer.  This curiosity of nature is almost like something from Ripley’s Believe it or Not.  But this predation has been recorded many times–I found half a dozen photos on google images of bobcats successfully killing adult deer, though they more often kill fawns.

Bobcats are one of the most common species of carnivores in the Pleistocene fossil record, evidence they outnumbered all other species of cats in North America.  In Georgia bobcat fossils have been excavated from Ladds, Yarbrough Cave, and the Isle of Hope site.  Bobcats evolved from a holarctic species of lynx during the Pliocene.  Early and middle Pleistocene bobcats were larger than late Pleistocene and modern bobcats.  I hypothesize that evolving to a reduced size helped them avoid competition with dire wolves, saber-tooths, and jaguars over larger prey items.  As I’ve noted before on this blog, the biomass of smaller animals such as rabbits and rodents far outweighed the biomass of large herbivores during the Pleistocene, even though it’s more famous for megafauna.  Bobcats survived the extinction of the megafauna because their smaller size enabled them to thrive on the smaller creatures that were still abundant.  During the Pleistocene megafauna populations fluctuated greatly but smaller prey items were always available.  I also hypothesize the bobcat’s ferocity, as evident when they attack much larger deer (and dogs as the above newspaper article relates), comes from an inherited mind-set.  The bobcat may have evolved into a smaller feline, but it still thinks of itself as a 75 pound cat rather than a 40 pounder.

Reference:

Griffin, John

“Bobcat Ecology on Developed and Less Developed Portions of Kiawah Island”

UGA Thesis 2001

 

A Polar Bear (Ursus maritimus) Fossil in Breck Smith Cave, Kentucky?

September 16, 2012

Several old publications mention a polar bear fossil that was found circa 1916 in Breck Smith Cave which is 8 miles west of Lexington, Kentucky.  Apparently, 3 women who were exploring the cave discovered the bones, and they took them to an “authority” at the University of Kentucky. He identified them as polar bear.  Unfortunately, the specimen was never described in the scientific literature, and as far as I can determine, the ownership of this unique fossil has long been forgotten.  Because the presence of polar bears in northern Kentucky would have interesting ecological implications, I would like to locate the fossils and have a modern expert examine them.  If anyone knows where they are, please contact me.

Polar bear killing a seal.  If the fossil specimen from Breck Smith Cave was correctly identified, seals must have also been present in the Ohio and upper Mississippi Rivers during the Ice Age.  Walrus fossils have been excavated from 2 sites in Michigan.  As far as I know, those are  the closest pinniped fossils to Breck Smith Cave.

From the available information I don’t know for sure who the “authority” was that identified the polar bear fossil (or fossils), but I suspect it was Arthur Miller, head of the Kentucky University Geology Department from 1892-1925.  I strongly suspect he misidentified the specimen because the associated fossils imply a temperate environment.  Bones of raccoon, gray fox, woodchuck, wolf, bison, and man were found in the cave with the supposed polar bear fossil.  Today, polar bears are exclusively found in arctic marine environments.  I think it’s more likely the specimen is from a grizzly bear (Ursus arctos) or even a black bear (Ursus americanus).  Grizzly bears are closely related to polar bears and occasionally interbreed with them in the wild and in captivity.  A grizzly bear fossil was found at Welsh Cave as I related in my last week’s blog entry about the Kentucky Bluegrass Country.  However, there must have been a specific diagnostic feature for the scientist who identified the specimen to suggest the fossil specimen was from a polar bear.  Polar bears are almost entirely carnivorous, and their teeth are quite different from those of grizzly and black bears.  If he made the diagnosis based on teeth, he may have been correct.  There’s also the slight possibility that a man carried the polar bear fossil from the arctic to Kentucky.  Maybe he considered it a magic talisman of the great white bear.

Let’s assume the identification is correct, and it was not carried for a thousand miles by people traveling from the arctic to Kentucky.  How did polar bears, a species that depends largely on seals and whale carcasses, live in northern Kentucky?  Even during the Ice Age, northern Kentucky was not exactly polar bear country.  The Laurentide Glacier reached southeastern Ohio during the Last Glacial Maximum, but northern Kentucky was mostly prairie with fingers of boreal forests then.  Glacial advance during the Illinois Ice Age 100,000 years earlier than the most recent one was greater but still barely reached the Ohio River.  If polar bears did range into northern Kentucky during the Ice Ages, seals, their favored prey, must have been present on the Ohio and upper Mississippi Rivers.  Fossil hunters may want to look for seal specimens on the river bottoms here.

It’s not surprising that a scientist could have misidentified fossils from the Ursus genus.  Recent studies of the Ursus genome show a close relationship between black bears, grizzly bears, and polar bears.  (Grizzly bears and brown bears are one and the same species.) The first study of polar bear DNA determined they diverged from grizzly bears ~130,000 years ago.  Coincidentally and conveniently, this corresponds with the earliest known polar bear fossil which is from Norway and dates to ~130,000 BP.  A second study of polar bear DNA wasn’t as convenient–it suggested polar bears diverged from grizzly bears closer to ~600,000 years BP and as a species was much older than from what’s known in the fossil record.  Polar bears live in an environment where fossils are rarely found.  Most arctic fossils are deeply emerged in frigid waters, probably never to be found.  The most recent study of Ursus genetics looked at the whole genome, and it paints a much more complicated picture.  This study found that grizzly, black, and polar bears all diverged from a common ancestor between 4-5 million years ago.  This corresponds temporally with the beginning of the Pliocene when Ice Ages began occurring, causing continental changes in the environment and creating differentiating habitats for new species of bears.  Though black bears and grizzly bears diverged ~5 million years ago, the genetic evidence indicates these 2 separate species occasionally interbred until about 100,000 BP.  The genetic evidence also indicates that although grizzly bears and polar bears diverged as long ago as 5 million BP, these 2 species have periodically interbred in the past and they still do.

A second generation polar bear-grizzly bear hybrid.  A genome wide study suggests grizzly  and polar bears diverged about 5 million years ago but periodically interbreed.  The genome of brown bears living on the Alexander Islands in Alaska is made up of 5%-10% polar bear DNA.  Curiously, grizzly and black bears also diverged about 5 million years ago and periodically interbred until about 100,000 years BP.  Maybe that explains why Pleistocene black bears were as big as modern day grizzlies.

Polar bears probably interbreed with grizzly bears more frequently  during phases of global warming when their favorite habitat shrinks, and they come into contact more often.  Hybrids raised by grizzly mothers have a greater chance of survival because they learn to survive in a more varied habitat.  Middle Pleistocene polar bears were more genetically diverse than they are today, perhaps because the cycles between Ice Ages were shorter during this time period than they were in the Late Pleistocene.

References:

Brown, Joseph Stanley

GSA Bulletin 33 1922

Cooper, C.L.

“The Pleistocene Fauna  of Kentucky” within The Paleontology of Kentucky edited by W.R. Jilson

The University of Kentucky Press 1931

Webb, Miller et. al.

“Polar and Brown Bear Genomes Reveal Ancient Admixtures and Demographic Footprints of Past Climate Change”

PNAS 2012

http://www.pnas.org/content/109/36/E2382/1

The Kentucky Bluegrass Country

September 12, 2012

Some specimens excavated from the Little Kettle Creek fossil site in Wilkes County, Georgia suggest a climate phase at the time of their deposition similar to the present day climate of the Kentucky Bluegrass Country.  https://markgelbart.wordpress.com/2011/03/17/little-kettle-creek-the-only-pleistocene-fossil-site-in-the-piedmont-region-of-southeastern-north-america/       Bog lemmings reach their present day southern range limit in northern Kentucky, and red backed voles occur in cool north facing slopes of the southern Appalachians.  Yet, both of these species lived in central Georgia during some portion of the last Ice Age.  Moreover, evidence from catfish bones also implies much harsher winters than are known in Georgia today.  Rural areas of the Kentucky Bluegrass Country, particularly horse pastures with centuries old trees growing in them, are considered relics of the kind of savannah woodlands that predominated in southeastern North America during much of the Pleistocene.  Accordingly, this intriguing similarity between the present day Bluegrass Country and Pleistocene central Georgia inspired my research for this blog entry.   However, there are some important differences between the 2 regions.

Map of the Kentucky Bluegrass Country.  The present day climate here is a close analogue to some climate phases of the Ice Age in central Georgia.

The geology of the Kentucky Bluegrass Country causes a differing soil chemistry from that found in most of Georgia.  The inner bluegrass region rests on top of ancient limestone, making the soil basal while most of Georgia’s soil is acid.  The limestone orginated from Paleozoic Age coral reefs that ringed islands resembling those of the modern day Bahamas.  Over time geological processes turned all that coral into limestone.  The underlying limestone  makes the soil of the bluegrass region among the richest in the world.  The soil is high in calcium and other minerals that help plants grow and the animals that eat these nutritious plants are healthier than those from other regions, explaining why this is good land for raising horses.  Most of Georgia’s soil was never nearly this fertile, even before agriculture wore out the land.  The underling rock in the outer bluegrass region is shale.  Shale is merely fossilized mud.

Note the spectacular 400 year old bur oak in the top left photo. Bur oak is a characteristic species of the Kentucky bluegrass country.  I tried in vain to find as impressive a photo on google images, so I ripped this one off from the below referenced book.

Note the stand of giant bamboo cane in the bottom right photo.  Cane is a relic today, but at the time of European settlement it formed thickets that were as much as 20 miles long adjacent to streams and rivers.  Daniel Boone escaped from Indian captivity by running into one of these canebrakes.

The photo in the upper right corner is a typical feature of the Kentucky river with a steep bluff on one side and a floodplain on the other.  The photo in the upper left corner is of a spring that emerges above ground and seeps back underground.

The calcium rich soil fosters the growth of calciphiles–plants that grow best in this type of earth.  Pre-settlement forests consisted of sugar maple, black walnut, butternut, blue ash, white ash, Kentucky coffee tree, honey locust, black cherry, bur oak, chinquapin oak, Shumard’s oak, white oak, shellbark hickory, buckeye, hackberry, and mulberry.  Common undergrowth trees included great stands of pawpaw, crabapple, hazelnut, plum, twinleaf, blue cohosh, and slippery elm.  Many of these species are shade intolerant, and they grew in natural widely spaced groves similar to those described by William Bartram from his travels through Georgia in the 18th century.  The trees grew far enough apart to allow sunlight to reach the ground, allowing a wide variety of grasses and herbs to flourish.  A few of the common species found in the pre-settlement savannah woodlands were buffalo grass (Panicum sp.), the now endangered buffalo clover (Trifolium stoloniferum), wild rye (Elymus villosus and virginica, not the European grain), wild peavine (Amphicarpa bractenta), the edible wild bean (Phaeseolus polystachios), goldenrod (Solidago sphacelata), and many calcium-loving ferns, sedges, and wild flowers.  Giant bamboo cane (Arundinaria gigantea) grew in thick stands along streams and rivers.  One stand of bamboo was estimated to be 20 square miles in extent.

The Kentucky River washes away some of the rich soil on the floodplain, resulting in thinner, poorer soils along its margin.  This area sported a somewhat different composition of trees that included sycamore, white oak, elm, and tulip with an undergrowth of dogwood.  Red cedar, now a more common tree in second growth forests here, grew on rocky bluffs.

European settlers rapidly destroyed much of this beautiful environment.  They cut down most of the trees and converted most of the rich cane land into pasture.  They introduced species of grasses and herbs that outcompeted native plants.  They killed most of the sugar maple trees by cutting big chunks out of the trees to harvest the sap instead of carefully tapping the trees in a way that would keep them alive.  They allowed their livestock to overgraze between the trees, eliminating regenerating trees, reducing pawpaw stands, and wiping out hazlenut, so that the latter is completely absent from the region today.  However, many of the bluegrass pastures host ancient pre-settlement trees that are still standing.  A 400 year old bur oak still lives in Bourbon County.  Other pastures consist of groves of blue ash, bur oak, and Kentucky coffee trees ranging in age between 200-400 years old. The pastures are remnants of savannah woodlands.  Mowing is preventing regeneration and eventually these old trees will die.  For this reason these relics are endangered.

Botanists are uncertain whether Poa pratensis, the species of bluegrass for which this region gets its name, is a native or an introduced species.  Bluegrass is also known as English grass, and it ranges into Eurasia and select areas of the Rocky Mountains.  The first settlers reported seeing bluegrass growing in Kentucky in the mid 18th century, and there is no ship’s record of it being imported that early.  This species may have had a natural Holarctic range, meaning that millions of years ago it spread across the Bering landbridge.

Ecologists think the trampling and grazing of great herds of bison and elk  shaped the savannah woodland environment here, and that fire was rather infrequent.  The rich land and abundant mineral licks attracted unusually large numbers of ungulates to this area.  The bison, elk, deer, bear, and passenger pigeons kept tree saplings naturally thinned, fostering the growth of widely spaced trees.  Fire must have occurred only rarely because sugar maple (a fire intolerant species) was formerly common here.  This ancient savannah woodland environment originated during the Pleistocene, though the plant and animal composition varied, depending upon the climate phase.  During interstadials and interglacials when deciduous trees were abundant, mastodons, giant ground sloths, deer, and long-nosed peccary thrived.  Both honey locust and Kentucky coffee trees bear leguminous pods that mastodons would have spread across the landscape in their dung.  Perhaps their abundance here along with pawpaws is evidence that mastodons made their last stand in the bluegrass country.

There is an excellent Pleistocene age fossil site in the region–Welsh Cave.  It was excavated in 1965.  Here’s the list of fossil speciments found here.  *denotes extinct species. # denotes species no longer found in the region

*dire wolf

#grizzly bear (southeasternmost known occurrence)

#badger

least weasel

*mammoth

horse

*flat-headed peccary

water shrew

pygmy shrew

short-tailed shrew

eastern mole

#snowshoe hare

#red squirrel

#spruce vole

yellow-cheeked vole

red-backed vole

meadow vole

pine vole

#porcupine

#thirteen lined ground squirrel

#pocket gopher

brown bat

pipistrelle

The radiocarbon date from the fossils found here was ~13,000 BP which translates to ~15,000 calender years BP.  The faunal composition suggests a prairie environment with fingers of boreal forests consisting of pine, spruce, birch, and northern hardwoods.  Superficially, it would have resembled the lowlands of the present day Yellowstone National Park in appearance.  Obviously, the preponderance of species that prefer (or preferred in the case of extinct species) open spaces indicates the fossils were deposited during the Last Glacial Maximum when hardwood forests were on the wane and grasslands were expanded because of the cooler drier climate.  The Welsh Cave site is the southeasternmost known occurrence of the grizzly bear.  13-lined ground squirrels lived in Kentucky until as recently as 600 AD.  Their remains have been found in Indian middens dating to then.

Two More Interesting Notes About Pre-Settlement Northern Kentucky

–A passenger pigeon roosting site in 18th century Shelbyville, Kentucky was estimated to be 120 square miles in extent.

–The Kentucky River, a tributary of the Ohio River, once was home to a freshwater species of cod, now restricted to more northerly localities.  The American burbot, also known as the eel pout, is called the “poor man’s lobster.”  Along with 2 species of sturgeon and the paddlefish, it’s been eliminated from Kentucky’s waters.

Reference:

Wharton, Mary; and Roger Barbour

Bluegrass Land and Life

The University of Kentucky Press 1991

Pawpaws, Favored Fruit of the Mastodons Part II

September 7, 2012

One of the first essays I ever wrote for this blog was about the pawpaw (Asimina triloba), a tree from a mostly tropical family of plants that grows and produces fruit in the temperate regions of North America.   https://markgelbart.wordpress.com/2010/10/01/the-paw-paw-a-favored-fruit-of-the-mastodon/  Some paleoecologists speculate that the pawpaw has a more localized distribution today than it did during the Pleistocene because the fruit seed is no longer spread across the uplands in the dung of now extinct megafauna such as mastodons and ground sloths.  It’s mostly found in moist river bottomlands where floodwaters distribute the fruit seed.  I’ve been wanting to taste a pawpaw for probably close to 30 years, but I never found any growing in Augusta, Georgia.  I did find some in Congaree National Park, but the fruit was not ripe yet.  So I offered a free copy of my book, Georgia Before People, to anyone who sent me some pawpaw fruit or seed.  It took a couple of years, but someone was kind enough to respond and send me 5 pawpaws.

Supposed range map of the pawpaw (Asimina triloba).  In 1970 the Mango variety of pawpaw was found from a wild tree growing in Tifton, Georgia, significantly south of what this map indicates.  Charles Wharton reported pawpaws were common in the alluvial and colluvial woods of the upper piedmont where water can carry the fruit seed.

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Indiana pawpaws shipped to Augusta, Georgia.

Each pawpaw had an average of 8 seeds.  I planted 9 seeds in pots.  After I used all of my available pots I  planted the rest directly in the ground.

One of the pawpaws was overripe and fell apart during shipping but the rest were perfectly ripe.  They taste very sweet and have the texture of a cooked sweet potato.  The aroma is faintly tropical.  It is an outstanding worthwhile fruit, considering the ones I ate were from uncultivated trees.  Uncultivated apples and pears by comparison are usually so poor in quality they are practically inedible.  Some horticulturalists are attempting to cultivate new varieties of pawpaws.  The main obstacle they face is the inability of the ripe fruit to keep for long enough to store in warehouses and ship.  I think there are now well over 20 cultivated varieties, including Sunflower which has orange flesh, and Mango from a wild tree found in Tifton, Georgia.  Photos from promoters of pawpaws show them split open and they suggest spooning out the flesh.  I found it easier to bite into them and spit out the seeds–the skin is edible.

Pawpaws are far more nutritious than bananas, apples, and oranges.  They have a complete protein which is unusual for a plant food.  They also have a high amount of monounsaturated fat–the healthy kind.  Their sugar content provides a balance with the fat and protein, making them an almost perfect complete food.  They are extremely high in Vitamin C, magnesium pottassium, and other minerals and have a decent amount of B vitamins and calcium.  Pioneers living in the woods of North America could have subsisted entirely on pawpaws from late August to early October–the season ripe pawpaws are available.  Some pioneers homesteading in cabins within mesic woods wandered through great stands of pawpaw trees and gathered the fruit in baskets while out hunting for their family’s supper.  When they sat down to eat a supper of pawpaws, they were enjoying a fruit that may have been eaten by dinosaurs.  50 million year old pawpaw fossils, dating to the Eocene, have been excavated in Mississippi.  It’s likely pawpaws or a related species are older than that and predate the K-T impact.

The Magic of Fall Fungi

September 3, 2012

My backyard smells like a rotten mushroom.  Mushrooms emerge in abundance when heavy rains follow a dry spell.  After a relatively dry July, almost 9  inches of rain fell in my yard this August, according to data from my rain guage.  A great variety of fungi live in the soil here.  They exist as web-like filaments underground.  Fungi filaments can be many square miles in extent.  Excessive moisture following long dormant periods cause the underground filaments to produce above ground fruiting bodies visible as mushrooms.  The mushrooms eventually spawn spores that spread via wind or in animal feces.  Below are some photos of the diversity of fungi I’ve found growing in my yard this past month.

Yellow house plant mushroom sharing space with a fig tree in a pot.  It’s toxic but scientists don’t know how poisonous it is–its toxicity has never been studied.

A whole colony of these mushrooms are growing on decaying vegetation in my backyard.  I think it’s a species from the Russula genus.  Emetic russula is poisonous.  I have seen squirrels eating this kind of mushroom but that does not mean it’s safe for human consumption.

I think this is the same species as the above photo but it’s growing in my front yard at least 60 feet from the other one, demonstating just how large fungi colonies can be.  Note the mold–fungus growing on fungus.

Artist’s fungus (Ganoderma applanatum) growing on a log I innoculated with shitake mushroom spawn.  The shitakes failed (so far), but artist’s fungus is thriving here.

I have no idea what species of mushroom this one is. 

This is a common puffball, I think.  Euell Gibbons claimed all young white puffballs are edible.  Poison puffball is black.

This mushroom looks like a mole’s ass.  I think that’s what I’ll call it–mole’s ass fungus.  I found nothing like it in any mushroom field guide nor on google images.

A big brown mushroom that again I can not identify.  Maybe there’s a mycologist out there who can help.  After a few days it turned to mush and smelled like liver.

Newly emerged unidentified white mushrooms.

There is no telling how old some of these fungi colonies are.  If as I suspect, my lot was never plowed but was instead used as a pasture because the soil is poor, these colonies might date to the Pleistocene.  Fungi help decompose organic matter, and they form symbiotic relationships with living plants.  The underground mycelium act as sponges absorbing nutrients and moisture, making these available for plant roots.  In return the plants provide fungi with sugar and nutrients produced by photosynthesis. 

Northern flying squirrels and red backed voles help spread fungi spore throughout forests where they range.  Both of these species ranged as far south as central Georgia during the Ice Ages.  A majority of their diet consists of fungi which they spread in their feces.  Deer also spread fungi spores.  The rodent and deer scat provides a perfect environment for the spores.  Scat has yeast, bacteria, and the properties of anti-freeze that fungi spores need to stay alive.

Northern flying squirrel (Glaucomys sabrinus).  Southern flying squirrels (Glaucomys volans) eat the same foods as northern flying squirrels but the quantities differ.  The former eat a greater amount of fungi, including underground truffles, while the latter eat more nuts and acorns.  Northern flying squirrels used to range as far south as central Georgia during the Ice Age, but their range is retreating even today due to global warming.  Squirrels help spread fungi spawn.

I’d never dare eat a wild mushroom.  Many species are dangerously toxic.  I’ve picked up some, though, and discovered they have a delicious aroma.  Later, I read that poisonous mushrooms shouldn’t even be handled.  Dried porcini mushrooms sold in most grocery stores are a perfectly safe substitute for wild mushrooms because they have the intense flavor gourmets seek when they go looking for edible wild mushrooms.  I have more than 1 cookbook in which the author claims all puffballs are edible, but there is a species known as poison puffball, so don’t believe something is true just because it is printed in a book.

I did ingest hallucinogenic mushrooms when I was a college student some 30 years ago.  I worked a construction job for a day, and the contractor offered me money or a bag of mushrooms.  I chose the latter.  Among heads, they’re called “magic mushrooms” but in the south they’re commonly known as “shroon.” 

These look like the hallucinogenic mushrooms I ingested in college.  I did not find these growing in my yard.

The psychoactive chemical compound in magic mushrooms is psilocybin.  Over 190 species of fungi have psilocybin.  The effect is intense, more intense than LSD which is an extract of mold–another fungus.  However, a mushroom high dissipates pleasantly like a marijuana high.  An LSD high (or trip) is more like a plateau that does not dissipate, but instead drops the user like a sack of potatoes when it wears off.  LSD is exhausting and unforgiving.  I remember being on LSD and just wanting to be able to think normally again, but all I could do was wait for it to wear off.  Anti-drug propaganda films shown in high school health classes depict LSD flashbacks occurring years after a user took the drug but this is nonsense.  I think what they’re referring to is what happens near the end of a trip when the drug wears off completely, then briefly kicks in again, so that a user is in and out.  The user can wrongly assume it’s ok to drive before the drug is completely finished with them.  I knew a couple of guys who totaled their cars while on LSD, but thankfully did not suffer any injuries.

I remember on one occasion I shared my construction job mushrooms with a friend.  The trip got so intense I became nervous and could no longer continue to sit and drink beer with him in our usual fellowship.  I abandoned him and went to bed early, but calmed down enough to rejoin him, maybe 20 minutes later.  We looked at an Amazing Spiderman comic book–spidey’s second encounter with the lizard.  This issue was particularly colorful to a person under the influence of “shroon.”

I’ve retired from using all hard drugs, including liquor, but I still on occasion drink moderate amounts of beer or wine, and if I had a chance would still smoke marijuana.