Posts Tagged ‘mastodons’

Pleistocene Persimmons (Diospyros virginiana)

December 19, 2012

Every year, I gather persimmons from a tree growing on a narrow strip of land between an expressway and a mall parking lot.  I know enough to wait until early December before I harvest the fruit.  Though a few varieties do ripen as early as mid-September, most don’t bear ripe fruit until winter.  Many people unfairly dismiss persimmons because they’ve eaten unripe ones.  The tannic acid in an unripe persimmon gives a person the feeling of having a mouth full of cotton.  Persimmons look ripe to the unpracticed eye for several months before they are actually good to eat.  They must be soft and mushy to touch before one knows the sugar has replaced all the tannic acid.  The ripening process has nothing to do with frost, but rather length of exposure to sunlight. They need so many hours of sunlight to ripen that they usually aren’t ready to eat until after the first frost.

Shroom 023

I picked about 3 pounds.  I picked these on December 1st.  The fruit on the tree growing next to this one was still not ripe.  I had another photo I wanted to use, but decided not to post it because I didn’t realize my checkbook was in the background.  I didn’t think it was a good idea to have my account number on the internet.

Persimmons are very sweet and to me taste like perfumed dates.  I simply pop them in my mouth and spit out the seeds.  They are one of the most nutritious fruits in the world.  The food value of this fruit attracts many species of mammals including fox, possum, raccoon, and bear.

Possum eating persimmon.  They don’t swallow the seed and are not good dispersers of the fruit.

Raccoon reaching for persimmon.  They do swallow the seeds and are good dispersers for the fruit.

Possums are famous for loving persimmons, but they are not effective dispersers of the seed.  One study proved that possums rarely swallow the seed.  In this experiment possums were given 63 persimmons and only 1 seed was ingested.  Raccoons, foxes, and bears are better dispersers of the fruit because they do swallow the seeds and scatter them in their scats.  Another study found that persimmons were a favorite food of raccoons.  Raccoons chose persimmons over corn, crayfish, eggs, earthworms and 5 other items.

Persimmons are considered only slightly anachronistic, unlike pawpaws, honey locust, and osage orange–3 plants that were entirely dependent on extinct megafauna for dispersal. A mastodon likely gobbled down persimmons by the hundreds and spread them all over the landscape.  Persimmons have been found in mastodon dung excavated from the Aucilla River in Florida.  The tree can resprout vegetatively, so they could have withstood heavy proboscidean pruning.  However, persimmons are still  common  and not local in distribution like other more anachronistic species.  In abandoned fields in Georgia persimmon is almost as common loblolly pine, oak, and sweetgum–the pioneer trees of early forest succession here.

Persimmons are in the ebony family which includes approximately 200 species.  Most are tropical.  The American species and the closely related Asian species grow in temperate zones.  The both descend from a common ancestor that lived on both continents during the Miocene.  The only other common American species is the black sapote (Diospyros digyna) which grows in Mexico and Central America.  (A rare third species occurs in Puerto Rico.)

A large species of African persimmon is entirely dependent upon elephants for dispersal.  The fruit is also eaten by chimpanzees and gorillas, but the seeds are too large for them to swallow.  Only elephants are big enough to swallow the seeds of this species.

Elephants are the sole disperser of a large species of African persimmon.

Persimmon Bread

Here’s Euell Gibbons’ recipe for persimmon bread.  It is excellent and I make it every year.

Beat 1 and 1/2 sticks of softened butter with 1 cup of sugar.  Add 1 cup of persimmon pulp and 2 beaten eggs, and 1/2 cup of chopped nuts.  Add 2 cups of bread flour and 1 teaspoon of baking powder.  No liquid is required.  Spoon the batter in a well-greased loaf pan and bake for 1 hour at 325 degrees.

It is tedious to separate the seeds from the pulp.  It takes about 40 wild persimmons to equal 1 cup of pulp.  I don’t even bother removing the skins, and a few seeds always end up in the bread.  It would be convenient to find a female persimmon tree that was left unfertilized.  Unfertilized female persimmon trees bear seedless persimmons.  I know of a persimmon tree that bears seedless persimmons, but it grows on an island in Woodbridge Lake in Evans, Georgia and is only accessible via canoe.  The lake must isolate it from pollination.  Grocery store persimmons come from female trees that are commercially grown in isolation from male trees.  They are all seedless, but I can’t bring myself to pay money for a fruit I can obtain for free.

Reference:

Barlow, Connie

“The Ghosts of Evolution: Nonsensical Fruit, Missing Partners, and Other Ecological Anachronisms”

Basic Books 2000

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Riverbluff Cave and Other Missouri Fossil Sites

December 14, 2012

The terrorist attacks on September 11, 2001 overshadowed the discovery of a remarkable fossil site in southeastern Missouri that occurred on that very day when a road-building crew uncovered Riverbluff Cave.  This cave is 220 feet long and the fossiliferous Pleistocene-age sediments were 18 feet thick.  On the first day of discovery workers found 15 foot high claw marks made by the extinct giant short-faced bear (Arctodus simus).  I posted a photo of those marks on the blog entry just previous to this one.  The cave is now closed to the public and only scientists with permits are allowed to study inside, though there is a public museum dedicated to the find.

Riverbluff Cave, Missouri.  The cave is closed to the public.  It’s a beautiful rock outcropping.

Fossils apparently began accumulating in Riverbluff Cave about 970,000 BP.  The fossil deposition lasted until 55,000 BP when a rockfall sealed the cave.  Scientists found mammoth bones dating to 660,000 BP here.  The website for the Riverbluff Cave Museum erroneously reports this as the oldest mammoth fossils found in North America.  This claim is not even close.  Mammoth fossils dating to 1.36 million years ago were found in Bruneau, Idaho 60 years ago, and I think there have been mammoth fossils found in Florida that are older than that.  This early mammoth species is known as the southern mammoth (Mammuthus meridionalis).  However, Riverbluff Cave does have some unique features found nowhere else.  Scientists found 25 beds scratched out by bears that formerly denned here.  This is also the only place in the world where tracks of the extinct flat-headed peccary (Platygonus compressus) are still intact.  Strange as it may seem, fossil millipedes dating to the Pleistocene were unknown from that era until they were discovered here.  In addition to these unusual features, the cave offers scientists a mountain of data, including bear and peccary coprolites, hair from extinct mammals, and scores of bones from large and small mammals, birds, reptiles, and amphibians.  Plus, the rocks forming the surface of the cave contain Paleozoic echinoderm (starfish) fossils.

Claw mark made by an extinct species of lion–Panthera atrox.

Hoof marks made by flat-headed peccaries.

Fossil sites in southwestern Missouri

There used to be 6 springs on a Pomme de Terre River terrace in southwestern Missouri before construction of a dam flooded them.  Luckily, scientists were able to study each in detail in advance.  These springs acted as bogs that attracted and preserved many species of animals but especially semi-aquatic mastodons whose remains were so abundant that scientists could thoroughly study changes in their anatomy over time from specimens excavated here.  Pollen, plant, and animal fossils accumulated in Jones Spring beginning 75,000 BP and lasting until the present, providing an almost continuous ecological record.  During the middle of the Wisconsinian Ice Age, a warm interstadial allowed hardwood forests to flourish on rich soils, while jack pine predominated on thin and sandy soils in this region.  Jack pine no longer occurs south of Michigan.  Macrofossils of oak, maple, dogwood, plum, cherry, elm, hickory, honey locust, osage orange, ash, juniper, and jack pine were excavated from Jones Spring. Pollen indicates an environment of 20%-30% pine, 10% oak, 5% grass, 5% composities, 5% ragweed, and 35% other plants.  This composition of species suggests an environment prone to frequent fire.  Osage orange and honey locust, not coincidentally, bore fruit dependent on mastodons for propagation, explaining their abundance here.  Later, as the climate cooled, spruce forests replaced the oak and pine woodlands, but by the latter stages of the Ice Age, oak and other hardwoods began to recolonize the region, and they co-existed with spruce in forests that have no modern analogue.  Jack pine never recolonized the region, demonstrating the haphazard nature of plant distribution.  Vertebrate fossils found here included mastodon, mammoth, Harlan’s ground sloth, camel, horse, donkey, tapir, long-horned bison, woodland musk-ox, saber-tooth, raccoon, ducks, alligator, and box turtle.  The presence of alligator, which no longer ranges this far north, may be evidence of warmer winters during the mid-Wisconsinian interstadial than occur here today.  However, it’s possible alligators simply haven’t recolonized the region since the LGM.

There were 2 Trollinger Springs.  The remains of at least 15 mastodons were excavated from these springs in addition to woodland musk-ox and stilt legged deer (Sangamona fugitiva).  Koch Spring was excavated in 1843, but most, if not all the fossils, were shipped to European museums and are now lost.

Jeffrey Saunders posing behind some mammoth bones found at Boney Spring, Missouri.  He co-authored one of my most favorite scientific papers I’ve ever read.  From data they analyzed that came from 6 springs on the Pomme de Terre river terrace, they were able to reconstruct what the environment was like during the mid to late Wisconsinian Ice Age in Missouri.

Fossils from Boney Spring date to the LGM.  This spring hosted the greatest variety of animal fossils found in all the springs.  Scientists even found seed shrimp and insect fossils in Boney Spring.  One of the insect species (Ocophora) is a boreal rove beetle that no longer occurs this far south.  Scientists catalogued the bones from 2 species of fish, 4 of amphibians, and 7 of reptiles.  Many small mammals left fossil evidence at Boney Spring–fox squirrels, woodchucks, flying squirrels, chipmunks, gophers, and bog lemmings.  Larger mammals such as giant beaver, Harlan’s ground sloth, horse, tapir, and white tail deer left bones here as well.  The remains of at least 31 mastodons rested here until they were excavated prior to reservoir inundation.  Pollen from one of the mastodon tusks contained 26%-30% spruce, but also substantial amounts of oak, willow, alder, elm, and tulip.  This particular mastodon must have died during the latter stages of the Ice Age when hardwoods were recolonizing the land from spruce forests.

Truman Lake now covers those amazing springs where so much paleoecological information was gleaned.

References:

King, James; and Jeffrey Saunders

“Environmental Insularity and the Extinction of the American Mastodon”

Quaternary Extinctions: a prehistoric revolution edited by Paul Martin and Richard Klein University of Arizona Press 1984

http://www.riverbluffcave.com/

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.

Mastodons, the Stewards of Wild Pleistocene Vinyards

August 21, 2011

I couldn’t find an illustration of mastodons yanking down grape vines from tree tops.

Grape vines co-evolved with Pleistocene megafauna.  Today, they thrive and produce fruit most abundantly when humans prune them aggressively.  Grape vines do not produce fruit on old wood, so pruning is necessary for them to bear.  In North America before man colonized the continent, mastodons were the stewards of wild Pleistocene vinyards.  Grape vines covered many square miles of forest, especially during warm wet interglacials and interstadials.   When Europeans felled virgin timber they also removed century old grape vines with 12 inch trunks–a rare site today but something mastodons must have encountered frequently.  Young grape vines will colonize second growth and oftentimes reestablish themselves as a dominant component of the local flora.  They are resilient plants adapted to being ripped apart and chewed upon by beasts such as mastodons and ground sloths.  A herd of mastodons chomping down on a grape vine wouldn’t necessarily stamp it out of existence.  Grapes not only produce seed-bearing fruit on new shoots, but  they can also spread vegetatively.  Vines growing on the ground get covered with leaves and forest litter.  The buried vines then sprout new roots and new vines can spring up quite a distance from the parent.   A mastodon could rip apart a vine, carry it or toss it many yards away, and if the vine got covered by leaves and moist dirt, it wouldl survive as a new individual.  So even if no animals eat the fruit and spread the seed in their dung, grape vines will still spread like an unstoppable alien plant from a science fiction movie.  By spreading vegetatively, they can even survive late spring freezes which prevents any fruit production. 

These grape vines sprouted from roots originating from vines extending from another grape vine that I’m growing on a fence.   Pine straw shedded from nearby trees covered grape vines growing on the ground.  Under the litter they sprouted more roots and then more vines.  The city sent me a registered letter declaring this a code violation.  It doesn’t seem like the government has the right to tell people how big plants they grow on their private property can get.

This is the after picture.  I did clear up the contested area, but it felt like I was fighting a plant monster from a science fiction movie.

It’s no surprise that grape vine material was one of the plants found in fossil mastodon dung at the Aucilla River site in north Florida.  Mastodons ate a wide variety of vegetation, and grape is a comparatively easy plant to digest because it is adapted to survive via rapid vegetative growth rather than poisonous defense.   There’s little evidence of grape in Pleistocene pollen studies.  Grape pollen is not widely dispersed, so when it is found, it’s assumed to have occurred locally, next to the actual site.  Grape pollen was found to be abundant at the Sandy Creek Run site on Warner Robins Air Force Base near Macon, Georgia, but only for the last 7,000 years.  It’s absent at that site before then.  (The site has a pollen record from the present to 13,000 BP and from 25,000 BP-30,000 BP.)

Five species of wild grape grow in Georgia today and likely grew here during the Pleistocene, being abundant during interstadials and interglacials but limited to local relic status during cold dry stadials. 

Summer Grape, pigeon grape–Vitis aestivalis

Supposed to be common in Georgia, but I’ve never seen one here.  They resemble concord grapes in appearance.

Possum grape–Vitis baileyana

Supposed to be rare in state, but it’s the only one other than muscadine I’ve ever seen here.  They’re a small black grape. 

River grape–Vitis riperia

Considered uncommon in state.  Another blue grape similar in appearance to Concord.

Muscadine grape–Vitis rotundifolia

Very abundant in state.  I can almost always find this species growing wild in any second growth or overgrown vacant lot.  Or my backyard where this sprouted up under an oak tree.  The wild variety that grows in Georgia is a purple grape when ripe.  Scuppernongs are a greenish/brown variety of muscadine, originally found growing along the Scuppernong River in North Carolina by early European explorers (Giovanni Verrazzano in 1504 and Sir Walter Raleigh in 1585).  Cultivated muscadines are my favorite grape to eat, but I don’t ever buy them in chain supermarkets–they’re always picked too early and have no flavor.  Instead I buy them at fruit stands or eat the ones I grow myself.

These are my two cultivated scuppernong vines.  They’re 20 years old.

Muscadines have tough skins and seeds but they’re the sweetest grapes and by far have the best and most distinctive flavor.  Most grapes sold in the store, such as Thomson seedless and Flame Red, are bland by comparison.

Four varieties of muscadines grow in my yeard.  Wild muscadines sprout naturally.  One of the vines I planted is the original scuppernong variety which is excellent for a wild grape but not nearly as good as the improved variety that I planted next to it.  I can’t recall the name because it has been so long since I planted it.  The latter is bigger, sweeter, and not as tough.  Last winter I planted a variety known as the giant black muscadine but it hasn’t produced fruit yet.

A cultivated variety of scuppernong is on the left, the original wild kind is on the right.

Experts say muscadines have no pests but this is not true.  Yellow jackets and wasps will destroy about 1/3 rd of the fruit every year.  Some years my vines have produced over a gallon of grapes, not counting ones eaten by yellow jackets.  When picking, one must be careful not to grab a grape in which a stinging insect has burrowed.

Note the blue-winged wasp (Scolia dubia?) feasting on one.

I made good scuppernong wine once.  It was dry, not sweet.  I put a teaspoon of cinnamon in one bottle and let it age for a few years for the best spiced wine I ever drank.  The muscadine wine sold in stores is terrible–usually sickeningly sweet and harsh.   Young grape leaves are also a gourmet edible.  Add 20 young grape leaves to stew with beef for a unique fruity but not sweet flavor.  They can also be stuffed with rice, ground beef, or mushrooms.

Fox grape, winter grape, chicken grape, frost grape–Vitis vulpina

Considered an occasional grape in the south.  It’s another blue grape like Concord.  It doesn’t become sweet until frost when it begins to decompose.

Most supermarket grapes are descendents of crosses between some of the above mentioned grapes and varieties of European grapes–Vitis vinifera.  Worldwide, all grapes are grown on American grape rootstocks which are resistant to a disease that wiped out Vitis vinifera rootstocks.

Peppervine and Virginia Creeper are also in the grape family.  The latter is a tenacious vine too.

Mastodons and Wild Plum Thickets

May 30, 2011

I found this thicket of wild Chickasaw plums in south Richmond County, Georgia.  The thicket covers at least 2 acres.

Wild plum thickets abound over much of North America.  They’re a pioneer species, growing extensively in old overgrown fields before other trees eventually shade and thereby outcompete them.  The lifespan of a plum tree seldom exceeds 20 years anyway, which is the length of time a plum thicket lasts during its stage of forest succession.  Plum thickets are a common site along roadsides in Georgia and other southeastern states.  For various reasons highway crews often clear corridors on the sides of roadways, and plums thrive in the sunny locations when overstory trees ares stripped or removed.  Today, birds and small mammals such as oppossums, raccoons, and gray foxes eat the fruit and spread the seeds in their feces.  American Indians also extensively planted plums around their settlements.  The variety of plum in the above photograph is known as the Chickasaw plum (Prunus angustifolia), and it is believed to have been originally cultivated by the Chickasaw Indians.  They spread the variety east from their early settlements.

There are 3 species of wild plums that range into Georgia, including south Richmond County where I found the plum thicket pictured above.  I used photographs from google images to compare and distinguish between the 3 and determined that the ones I found were probably Chickasaw plums, though I’m not a trained botanist, so I don’t know for sure.  The other 2 species are the American plum (Prunus americana) and the hog plum (Prunus umbellata).  I harvested a pint of the Chickasaw plums (I could’ve collected bushels.)  They are as sweet and  tasty as the best quality cultivated plums one can buy at a supermarket.  The only drawback is the small size–they’re a little smaller than cultivated cherries and the fruit to pit ratio is even smaller.

Picture of mastodons from google images.

Photo of Mastodon dung recovered from the Aucilla River.

Scientists examining 14,000 year old mastodon dung from the Aucilla River in north Florida found plum pits.  Chemical tests of fossil mastodon bones found at the site determined that mastodons wandered back and forth from north Florida to central Georgia.  These wide-ranging behemoths spread fruit and seeds of many plant species far and wide.  Most of the seeds that went through their alimentary tracts were not only still viable, but they had the added bonus of being encased in fertilizer when excreted.  (See also my blog entry “Paw Paw: Favored Fruit of the Mastodon” which I think is either in my May 2010 or April 2010 archives.)

The dynamic landscape of the Pleistocene included natural environments in all stages of forest succession.  Disturbances and atmospheric conditions such as fires, storms, megafauna foraging, insect damage, disease, floods, beaver activities, drought, and low CO2 levels contributed to frequent formation of meadows, prairies, and savannahs–all suitable environments for plum thickets.  With mastodons (and giant ground sloths) facilitating their spread, plum thickets must have been just as common then as now, if not more so.

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This is an addendum to my last week’s rant about the environmental destruction that white slave-owners inflicted upon Georgia in the early 19th century.  My favorite poem is the lyrics to the rock group, Rush’s song “The Trees.”  Rush is a fantastic group, if you can get past the high voice of the lead singer.  It’s amazing that just 3 people can put out the amount of sound they do.  Anyway, here are the lyrics.

“The Trees” by Rush.

There is unrest in the forest

There is trouble with the trees

For the maples want more sunlight

and the oaks ignore their pleas

The trouble with the maples

(and they’re quite convinced they’re right)

They say the oaks are just too high

and they take up all the light

But the oaks can’t help their feeling

if they like the way they’re made

and they wonder why the maples can’t be happy in their shade

There is trouble in the forest

and the creatures all have fled

as the maples scream “oppression!”

and the oaks just shake their heads

So the maples formed a union

and demanded equal rights

“The oaks are just to greedy; we will make them give us light”

Now there’s no more oak suppression

for they passed a noble law

and the trees are kept all equal by hatchet, axe, and saw

The Paw Paw, a Favored Fruit of the Mastodon

October 1, 2010

A large exotic fruit used to be a common component of North America’s virgin bottomland forests.  The paw paw (Asimona triloba), also known as the prairie banana, the Hoosier banana, the Michigan banana, and the custard apple is the only temperate member of a tropical family of fruit trees.

Paw paw fruit cut in half.

It looks delicious and is related to the cherimoya which can occasionally be found in some supermarkets.  Reportedly, paw paws taste like banana custard, a rich flavor that some love but others find too cloying.  Unfortunately, when shipped, it turns to brown mush, so unless the curious epicure has a tree in their neighborhood, they’re out of luck.  I’ve wanted to try this fruit for decades but have been frustrated–none grow in the second growth woods around Augusta, Georgia.  I did come across some on a hike through the Congaree Swamp in South Carolina many years ago, but the fruit wasn’t ripe in July–it ripens in September and October.   I have tasted cherimoya which is flavored like a cross between a pear and a pineapple.

Paw paws are still found in the wild today but are rare because they require shade to grow.  98% of North American forests have been cleared at one time or another, and once the virgin forest canopy is eliminated, paw paws don’t return.   Horticulturalists are breeding the trees for home gardeners, however.

Paw paws have large seeds that can go right through an animal’s digestive tract without being destroyed.  A number of scientists believe this species was dependent on the alimentary tracts of mastodons and giant ground sloths for dispersal.  No herbivore living in North America today is able to swallow the seeds whole.  Paw paws are only found in the wild alongside rivers and streams, despite growing well on upland sites when transplanted by humans.  Following the extinction of the megafauna, flooding was the only way the seeds could spread, explaining why they’re only found in the wild near waterways.  But during the Pleistocene, when mastodons and sloths ate the fruit, they carried them to upland sites and defecated the viable seeds there, so it’s likely this fruit had a more continous range then than it does today. 

Fossils of paw paws are known from as early as 50 million years ago during the Eocene.  It’s possibly an older species than that, being a food of dinosaurs as well.  Most of the family is tropical, but at least this species was able to adapt to temperate climates that began with the coming of the Pleistocene.

(I’ll send a free copy of my book to anyone who will ship paw paw seeds and/or fruit to me.)