Squirrels and Blue Jays vs Acorn Tannins

For over 10,000 years acorns were the most important source of food for Native Americans wherever oak trees were common.  Acorns are an important source of food for animals too for everything from mice to bison.  However, acorns contain tannins, a substance difficult to digest and even toxic for some animals.  For example horses that eat too many acorns may die. Oak trees rely on animals to spread their seed, but if too much of their seed is consumed, their populations will decline.  The nutritional value in acorns attracts hungry animals, but the tannins act as a semi-deterrent.  Acorns from species in the white oak family evolved a different strategy for coping with acorn predation than species in the red oak family.  White oak acorns contain less tannins and are more palatable, so squirrels and jays prefer these and spread them throughout the landscape, but they germinate as soon as they are buried in the fall.  When a squirrel or jay tries to retrieve them later, it is too late.  White oaks only lose acorns that are consumed immediately.  Acorns from oaks in the red oak family are high in tannins, but the tannins are concentrated in the bottom half of the acorn.  Squirrels gnaw on the top half and abandon the bottom half.  If enough of the bottom half is left, the acorn can still germinate, though red oak acorns don’t need to germinate until spring because squirrels and other animals don’t want to eat the part of the acorn with such an high concentration of tannins. This year the sand laurel oaks (Quercus hemispherica), the most common oak species in my neighborhood, are producing a bumper crop of acorns, and the squirrels are gnawing the tops of them but leaving the bottoms.

Squirrels eat the tops of acorns from oak trees in the red oak family.  These acorns, found in my backyard, are from a sand laurel oak. also known as Darlington oak.  The top part of acorns have less tannins which are hard for most animals to digest.  Nevertheless, squirrels risk death from the 8 cats that live in my backyard to exploit this food source.  Oaks can germinate from acorns with the tops gnawed off.

Squirrels fed a diet of just red oak acorns in an experiment ate less.  Blue jays fed a diet of red oak acorns in an experiment actually lost weight.  Squirrels living in a location with mostly red oaks must vary their diet with other foods such as white oak acorns, nuts, fungi, berries, and insects.  Blue jays fed a diet of red oak acorns and acorn weevil larva maintained their weight, showing how blue jays can survive in the wild on a diet of mostly red oak acorns because the infestation rates of acorns by weevil larva are high.  Incidentally, oak trees were able to quickly colonize New England and southern Canada following deglaciation at the end of the Ice Age because of the acorns that were spread by blue jays.

Tannins posed an obstacle for hungry Native Americans as well.  According to Euell Gibbons, Native Americans processed the acorns by boiling them in water to leech out the tannins.  It’s necessary to periodically change the water–a tedious process.  I tried this years ago with the sand laurel oak acorns in my yard.  After dumping the water out and replacing it 8 times, I got tired of the process and gave up.  The acorns were becoming less bitter, but still not palatable enough to eat in a satisfying quantity.  Native Americans with no modern day supermarkets were most persistent from necessity.

References:

Chang-Macoubrey, A;  A.E. Hagerman, and R. L. Kirkpatrick

“Effects of Tannins on Digestion and Detoxification Activity in Gray Squirrel (Sciurus carolinensis)”

Physiological Zoology 20 (3) 1997

Johnson, W., Libby Thomas, and Curtis Adkinson

“Dietary Circumvention of Acorn Tannins by Blue Jays: Implications for Oak Demography”

Oecologia 99 (2) 1993

 

 

Cave Paintings of Megafauna in the Amazon Rain Forest

Archaeologists have been studying ancient paintings on cave and rock shelter walls in Cheribiquete National Park for over 30 years, but last year they discovered an 8 mile stretch that includes rare images of extinct megafauna.  Cheribiquete National Park is located in Colombia and covers 17,000 square miles–the largest tropical forest park in the world.  The newly discovered rock shelter walls are illustrated with images of a giant ground sloth and young, horse, llama, macrauchenia, gompothere, and perhaps bear.  An extinct species of horse known as hippidion lived in South America over 10,000 years ago.  The llama depicted on the wall maybe an extinct or extant species.  All the images are crudely drawn and don’t depict adequate details to distinguish species identification.  These may be the only images of a gompothere and macrauchenia that have ever been drawn by people who actually saw them alive.  Gompotheres were a mastodon-like animal, similar to elephants, but nothing like a macrauchenia lives today.  Their closest living relatives are rhinos, horses, and tapirs; but genetic evidence suggests they diverged from those odd toed ungulates 66 million years ago when dinosaurs became extinct.  Macrauchenia were adaptable animals capable of living in many different kinds of habitats, and they likely occupied a giraffe-like ecological niche because they had long necks.  Fossil remains of macrauchenia are not found anywhere near Cheribiquete National Park, showing how inadequate the fossil record is.

Rock art paintings of pre-historic megafauna.  The art work is poor, but I think they depict a ground sloth and young, gompothere (an animal similar to a mastodon), a llama, an horse, and a bear or another ground sloth?, and a macrauchenia.  It looks like a man is hunting the gompothere (a juvenile?) with a club or atlatl.  It also looks like a man has his armed raised at the ground sloth, but the atlatl isn’t drawn.  In another image it looks like the man is stabbing the bear in the side.

The Natives must have used ladders to paint these figures on some of the rock shelters.  They are much higher than a human can reach.  Archaeologists used drones to photograph some of them.

Archaeologists suggest the natives scaled the high rock shelter walls to paint these images.  I think it is more likely they used ladders to reach these heights.  The paintings are thought to vary in age from about 15,000 years BP to the 16th century.  Apparently, natives stopped painting walls shortly after European contact perhaps because the culture shock of this interaction destroyed American civilizations.  The paintings themselves can’t be radio-carbon dated because the substance used was inorganic.  European cave paintings were drawn with charcoal and can be radio-carbon dated.

Some of the articles reporting this discovery are written by people who assume the presence of the animals depicted on the rock shelter walls is evidence of a different local environment during the Late Pleistocene than occurs there today.  This is not necessarily true.  Macrauchenia was a generalist species, and gompotheres likely preferred dense forests.  Clearings in the forest created by gompothere foraging may have sustained populations of horses and llamas.

In addition to the extensive rock shelter drawings, Cheribiquete National Park is home to 82 species of mammals (52 of them bats), an astonishing 410 species of birds, 60 species of reptiles, 57 species of amphibians, 238 species of fish, and over 200 species of butterflies.  Notable animals include jaguars, cougars, monkeys, armadillos, peccaries, tapirs, scarlet macaws, emerald hummingbirds, and harpy eagles.  The park has great potential as a tourist destination.  Unfortunately, it is also an hideout for thousands of FARC rebels.  FARC is an organization that basically is a bunch of communist gangsters who kidnap people for ransom and sell cocaine.  FARC battled the Colombian government for 40 years before finally signing a peace agreement recently, but the region is still not safe enough for tourism.

Pleistocene Alcohol

Our evolutionary ancestors accidentally got drunk when they binged on fermented fruit. This still happens to modern day species of monkeys and apes dependent upon fruit for a major part of their diet. In warm tropical regions the sugar in overripe fruits naturally ferments into alcohol when airborne yeast attaches to mold growing on the fruit. Modern humans discovered the fermentation process during the Pleistocene, though evidence is scant. The oldest known evidence of humans deliberately manufacturing alcohol comes from Raqefet Cave near Haifa, Israel, and it dates to 13,000 years BP. Archaeologists actually call the site a brewery. They found traces of barley and wheat beer in stone containers. Bread is likely just a byproduct of beer-making. The euphoria from alcohol consumption is addicting and far more motivating than satisfying hunger with bread when they had plenty of fish and venison to eat and could cook grains into cereal. Archaeologists also discovered evidence of early wine-making in northern China that dates to 9,000 years ago. This wine was made with honey, rice, and grape and/or hawthorn fruit. The latter is a small apple-like fruit that grows on scrubby bushes.

Natural yeast present in the atmosphere converts sugar to alcohol and also makes bread rise.

Location of Raqefet Cave and photos of the actual stone mortars used 13,000 years ago to store beer.  This ancient beer tasted nothing like modern beer.  It was sour and yeasty tasting.  Hops weren’t added to beer until the Middle Ages. Image from http://www.sci-news.com/archaeology/raqefet-cave-brewery-06412.html

Humans probably discovered, forgot, then rediscovered how to make alcohol dozens of times during the Pleistocene.  Humans have independently discovered the fermentation process at multiple sites around the world just in the past 6,000 years.  However, Pleistocene humans mostly used skins or wooden containers.  Evidence from such organic materials has long since decayed into dust, and the hypothesis that humans commonly manufactured alcohol for tens of thousands of years is impossible to prove.

I think alcohol is the most wonderful all-purpose medicine ever discovered by man.  For myself I prescribe alcohol to treat depression, anxiety attacks, obsessive compulsive disorder, Parkinson’s tremors, insomnia, back-ache, stomach-ache, tooth-ache, and erectile disfunction.  If I ever went to a doctor, he would prescribe 9 different drugs to treat each of these different problems.  Imagine how much that would cost.  I’d be spending half my life waiting in the pharmacy.  Oh yeah, and I also use alcohol to get high.  It’s what helps me get through the daily drudgery of my pathetic existence.

References:

Alex, Bridget

“The Search for the World’s Oldest Alcohol”

Discovery Magazine June 2019

McGovern, P. et. al.

“Fermented Beverages of Pre-and Proto- Historic China”

PNAS December 2004

 

Mastodon Ranges Fluctuated with Climate Changes

When I first began my blog I was unsure of my writing, so I submitted samples to an internet forum at absolutewrite.com.  One person criticized me for being redundant when I wrote about mammoths and mastodons because he wrongly assumed I was referring to the same animal.  I explained they were 2 completely different species: mastodons were a semi-aquatic animal that mostly ate leaves, twigs, and fruit; while mammoths were an upland species that mostly ate grass.  The lead author of a new study of mastodon genetics admitted he had the same misconception prior to studying the mastodon genome.  Emil Karpinski is a geneticist not a paleontologist, and his false assumption is understandable. Karpinski and his colleagues sequenced the complete genomes of 33 individual mastodon specimens and the partial genomes from an additional 12 individual specimens.  They found 5 major clades from different geographical locations including Alaska, Yukon, Alberta/Missouri, Mexico, and Virginia/Great Lakes.  A single specimen from Nova Scotia indicates the possible discovery of a 6th clade.  Genomes of mastodons from Alberta suggest a mixture of 3 different clades.  This region was a migratory corridor between the Cordilleran and Laurentide Glaciers during interglacial climate phases when Ice Sheets retreated.  Different populations came into contact here when mastodons expanded their range north during interglacials.

Image showing how mastodon ranges expanded during interglacials and contracted during Ice Ages.  Southern mastodons were more genetically diverse than northern mastodons because northern populations were extirpated during every Ice Age.  From the below reference.

Map showing location of mastodon specimens used in the genetic study.  Also from the below reference.

The genetic evidence clearly shows mastodons expanded their range into Canada and Alaska between Ice Ages, and the expansions occurred at least twice, probably more.  Spruce forests and wetlands in Alaska converted into dry grassland during Ice Ages–unsuitable habitat for a semi-aquatic species.  And of course Canada was covered with thick glacial ice–inhospitable to most life.

The authors of this paper express bafflement over why mastodons did not recolonize Alaska and Canada following the last Ice Age.  Wetlands and spruce forests expanded when glaciers retreated and left behind meltwater lakes and bogs.  The answer is obvious and no mystery at all.  Men disrupted mastodon migration routes and overhunted them to extinction.  Large areas of suitable mastodon habitat exist today all over North America, but they are devoid of these massive beasts because they could not co-exist with increasing human populations.

Reference:

Karpinski, E.; et. al.

“American Mastodon Mitochondrial Genomes Suggest Multiple Dispersal Events in Response to Pleistocene Climate Oscillations”

Nature Communications 11 Article 4048 (2020) 

https://www.nature.com/articles/s41467-020-17893-z

 

How to Make Dirty Rice and Jambalaya

Dirty rice probably originated as a creation of slave cuisine long before the onset of the Civil War. Slave-owners gave the poorer quality cuts of meat, even pig intestines, ears, and feet, to their involuntary servants. Slaves learned how to make these discarded animal parts taste good, and today these old treats are a component of Soul Food. In Louisiana rice was plentiful and slaves combined chicken offal with their rice ration into a popular dish most call dirty rice because the browned bits of meat give the rice a dirty appearance. Cajuns, also often living in poverty, adopted this economical dish, and now it is a famous part of Cajun cuisine.

I’ve studied many recipes for dirty rice, and they vary quite a bit.  Some call for 4 stalks of celery; others use no celery at all.  Justin Wilson, the late television chef, included canned cream of mushroom soup in his version.  His dirty rice is about the only recipe in his first book that doesn’t use cayenne pepper, but dirty rice definitely needs heat from cayenne.  Another late Cajun chef, Paul Prudhomme, wrote 2 recipes for dirty rice in his Louisiana Kitchen cookbook, including a seafood dirty rice, but in the Prudhomme Family Cookbook a recipe for dirty rice is not listed, though a recipe called “greasy rice” with hamburger and bacon basically is dirty rice.  The following recipe is my version of dirty rice, and I think it represents the best elements of the herb-flavored, starchy, meaty dish.

Cook 1 and 1/2 cups of rice in 3 cups of water with plenty of butter and salt.  While the rice is cooking brown 1 pound of Jimmy Dean’s sage sausage with 1 pound of ground chicken livers in a dry skillet under high heat.  Feel free to substitute any kind of ground meat, if you don’t like liver.  Use a spatula to break apart the meat. When the meat is no longer pink, smother it with 1 bunch of chopped green onions, 1 bunch of chopped parsley, 1 chopped onion, 1 chopped bell pepper, and 1 chopped stalk of celery.  Season to taste with salt and cayenne pepper.  Cover and cook until the herbs and vegetables are soft.  Mix the cooked rice with the meat and vegetables and let this sit together for 30 minutes with the skillet left on warm.  Dirty rice can be served as a main dish or a side and can be stuffed into poultry or bell peppers.  Boudin is a sausage made with a filling similar to dirty rice, though ground pork and pork livers are usually used.  Ground gizzards are also commonly used in dirty rice, but I think they are chewy and tough.  To make gizzards taste delicious, roll them in seasoned flour, brown them, smother them in onions, and cook them in a crockpot with a little water for 6 hours.  They will be nice and tender.

My dirty rice.  I left out the bell pepper (always optional in my opinion) and substituted ground turkey for ground chicken livers.  I prefer the latter, but my daughter doesn’t like liver.

One day when my daughter was about 6 years old she asked what was for supper.  I told her dirty rice.  She said, “I don’t want dirty rice.  I want clean rice.”  Then she didn’t like it because she didn’t care for the taste of liver.  Ever since, I’ve substituted ground turkey, called it Cajun clean rice, and she likes it just fine.

Dirty rice comes under the category of rice dressing when cooked rice is mixed with other cooked ingredients.  Jambalaya is different.  Jambalaya is like a dry soup when raw rice is cooked with other ingredients, and the rice absorbs the flavor of the items it’s cooked with.  Jambalaya originated in southern France and northern Spain  and is very similar to a Spanish paella.  There are a great variety of jambalayas.  I make chicken and sausage jambalaya most often, and this is how I make it.

Dice 1 pound of boneless chicken thighs and roll the pieces in flour seasoned with salt, black pepper, and cayenne pepper.  Brown the pieces in a little oil and set aside.  Chop 2 onions, 1 bell pepper, and 1 stalk of celery and sautee them in the grease the chicken was browned in.  Add 1 and 1/2 cups of raw rice and 2 crushed cloves of garlic to the vegetables and brown the rice. Season to taste with salt, red and black peppers, and thyme. Add 3 cups of chicken broth, stir the pan, scraping up the browned bits, and pour all of this in a casserole dish.  Add the chicken and 1 pound of smoked sausage such as andoullie or kielbasa cut into pieces.  Pour all this into a casserole dish.  Stir it so the rice is covered with liquid and the meats are evenly distributed.  Cover and bake in the oven at 350 degrees for an hour.  I made this 2 weeks ago but didn’t think to take a photo of it.

I make many other types of jambalaya.  Just plain chicken jambalaya is the easiest.  Season and brown 6 chicken thighs and place them on top of the rice, vegetables, and chicken broth in a casserole dish and bake.  Double sausage jambalaya uses 2 pounds of 2 different kinds of sausage instead of chicken and sausage.  Triple sausage jambalaya uses 2 pounds of 3 different kinds of sausage instead of chicken and sausage.  Shrimp and sausage jambalaya is not hard to make either.  The shrimp doesn’t need to be browned ahead of time, and I like to add tomato paste to it, but don’t worry about overcooking the shrimp.  I’ve found that baking them with rice for an hour does not overcook them, though many chefs claim it does.  Jambalaya is a great way to jazz up leftovers.  Turkey, ham, and mushroom jambalaya can be made from holiday leftovers using broth made from the turkey carcass.  Leftover pot roast can be converted into beef and cabbage jambalaya. (I like tomatoes in this 1 too.)  And leftover leg of lamb can be turned into lamb and raisin jambalaya.

Pleistocene Bush Dogs (Speothos sp.)

Scientists occasionally discover species as fossils before they are known to still be extant. The coelacanth and the Chacoan peccary are famous examples of this. Add South American bush dogs (Speothos venaticus) to the list.  A Danish paleontologist discovered bush dog bones in a Brazilian cave during 1839 and mistakenly thought he’d found evidence of an extinct species.  However, bush dogs still exist, though I can’t determine which western scientist first realized they were not extinct.  I’m sure native Americans were aware of their existence and may have kept some of them as pets once in a while.

Bush dogs range throughout the tropics from Brazil to Costa Rica.  Science was unaware of their existence in Costa Rica until last year, and they are not included in a book I covered on my blog recently–Mammals of Costa Rica by Mark Wainright.  Bush dogs are most common in Suriname and Guyana.  They prefer lowland tropical forest, wet savannahs, brush, and pasture habitats.  They reach a length of 2 feet long and weigh up to 18 pounds.  Bush dogs hunt in packs during the day, and their favorite prey are large rodents including pacas, agoutis, and capybaras.  The former 2 are uncommon in populated areas where natives hunt them for food, and this explains why bush dogs are also uncommon.  Competition with man has likely reduced bush dog numbers over the past 14,000 years.  Bush dogs have also been reported attacking peccaries, deer, armadillos, and rheas.

Bush dogs. They may be similar to many species of extinct primitive canids.

Bush dog range map.  This map doesn’t include documented sightings with photos taken in Costa Rica last year.

Canids first evolved in North America and were more diverse during the Miocene over 5 million years ago.  Cats from Eurasia then invaded the Americas and caused the extinction of many dog genera by outcompeting them.  A genetic study determined bush dogs are a sister clade with African hunting dogs (Lycaon pictus).  A species of hunting dog occurred in North America during the mid-Pleistocene.  Fossils of this species were found in Texas, and it is known as Troxell’s dog (Protocyon texanus).  Troxell’s dog also had short legs and dentition that resembled that of bush dogs.  This genetic study determined the ancestor of bush dogs diverged from the ancestor of African hunting dogs about 7.5 million years ago.  Amazingly, the bush dog’s closest relative lives on the other side of the planet.  Another genetic study found bush dogs are more closely related to wolves than they are to raccoon dogs or foxes.  However, they are not closely related enough to mate with wolves or domestic dogs and produce fertile offspring.

During the Pleistocene extant bush dogs co-occurred with another species of now extinct bush dog (S. pacivorus).  The latter species was slightly larger.  More carrion from extinct megafauna supported greater populations of predators then.

Monsters from Georgia

The natural world scares many people.  They freak out when they encounter a snake or a spider.  Not me.  I think they are interesting creatures and not something to fear.  For my annual Halloween blog article I could write about snakes or spiders or some ferocious dinosaur or pre-historic mammal that formerly roamed Georgia, but I don’t consider them monsters.  They killed for food, territory, or mates; and their behavior was largely instinctual.  The most terrifying monsters in the history of Georgia are our fellow human beings.  Below is a short summary of the most heinous monsters in Georgia history.

All Confederate soldiers were monsters.  They were fighting, whether they realized it or not, for the institution of slavery.  The Confederacy used extremist militias to take over an entire region of the country, sparking a 5 year conflict that included family members and relatives killing each other.  After the Civil War was over, southern sympathizers imagined and put into writing a revisionist version of what the conflict was about.  The war was over slavery and nothing else.  All the southern state legislatures and governors admitted they were seceding from the Union to preserve the institution of slavery. (You can find these historical documents online.) I believe their confessions. Later revisionists were simply a bunch of cry babies who wanted to pretend  southerners were victims, even though they brought their destruction down upon themselves.  The Confederate soldiers were not victims–they were all slave-owners, sons of slave-owners, or poor shmucks who aspired to be slave-owners.  

Confederate soldiers from Georgia. They claim they fought for States Rights.  Yeah, the right of states to keep slavery legal.

The next generation of Georgia monsters included racists who lynched innocent black people.  Now, most of the monsters on my list in this article look like ordinary people, but the monsters in the below photo look like refugees from the movie, The Texas Chainsaw Massacre.  Just think.  Their grandchildren post pro-Trump propaganda on Facebook today.  Facebook won’t let them use the N-word on their platform, but they have enough influence with Facebook for the platform to ban the word, White Trash, as if it is an equivalent.  (I am currently blocked from posting for 24 hours for saying conservatives = White Trash.)  It’s a false equivalency.  The word, White Trash, refers to a mindset more than a race.

Scary bunch of rednecks.

Eugene Talmadge served as Georgia’s governor from 1933-1937 and from 1941-1943.  He won re-election in 1946 but croaked of liver cirrhosis before he could serve in office a third time.  In the 1946 election he lost the popular vote but won the election anyway because Georgia had a rule that whoever won the most counties won the election.  Sound familiar?  Talmadge was an ardent segregationist who believed in slave labor.  He claimed to be a populist (like Trump) but supported the interests of wealthy landowners (like Trump).  He had striking textile workers arrested and put into POW camps.  He complained to President Roosevelt about New Deal public works programs that paid better than local farmers who were used to cheating poor people into working for obscenely low wages.  Talmadge wasn’t much of a reader, but he did read Hitler’s Mein Kampf 7 times, and he sympathized with both Nazi Germany and Imperial Japan.  In turn Germany’s Nazi Party praised Talmadge.  Talmadge attended KKK meetings and bragged about how he flogged black sharecroppers.  As governor, he fired de-segregationists serving on the University of Georgia’s Board of Regents, setting back integration there for decades.  Talmadge was also behind a lynching that resulted in the deaths of 2 young African-American couples.

Eugene Talmadge, Georgia’s governor for 2 terms during the 1930s and 1940s, read Mein Kampf 7 times and was praised by Germany’s Nazi Party.  He was an ardent segregationist.

William Calley commanded the platoon that murdered 504 old men, women, and children at the My Lai massacre in Vietnam.  He personally shot 22 of them.  Of the 14 men who took part in this war crime, he was the only 1 convicted.  He received a slap on the wrist–3 years of house arrest.  He should have been given the death penalty.  He went on to work in his father-in-law’s jewelry store in Columbus, Georgia.  Most of his customers hade no idea they were buying rings and wristwatches from a monster.

William Calley was found guilty of killing 22 innocent civilians during the My Lai massacre.

Wayne Williams raped and murdered at least 23 teenaged boys during the late 1970s in Atlanta.  He still claims he is innocent, and some of the victim’s parents believe him, but the evidence against him is overwhelming.  He posed as a talent agent to lure his victims into trusting him.  Police caught him throwing a body off a bridge into the Chattahoochee River in the middle of the night, and the murders suddenly stopped when he was taken into custody.  Moreover, 2 witnesses identified Wayne as the person who attempted to sexually assault them before they escaped.  Some additional murders attributed to Wayne may have been committed by other unknown monsters.

Wayne Williams raped and murdered dozens of black teenagers.  He still claims his innocence, though the police caught him throwing a body off a bridge and the killings stopped once he became incarcerated.

Pleistocene Foot, Hoof, and Paw Prints in New Mexico

(Note: Since I wrote this article, scientists have estimated these footprints are 21,000 years old.)

I worked alongside many young married men when the Augusta Chronicle employed me in their circulation department a few decades ago.  They all complained how their wives refused to have sex with them after having a baby.  My wife had a stroke during the birth of our daughter, and because of her disability I was forced to perform more mothering than most men.  Toddlers between the ages of 6 months and 3 years old go through a clinging stage.  All day long it seemed as if my child was constantly clinging to me or needing me to carry her.  By the time I got her to bed, I was so tired of human contact that sexual intercourse was the last thing I wanted.  Thus, I gained some insight into why the wives of my colleagues were not in the mood for romance after caring for a baby or toddler all day.  Evidence from over 11,000 years ago found in White Sands National Park suggests taking care of a toddler was a mood-killing chore even then.

Pleistocene Amberjack (Seriola dumerili)

I watched Food Paradise with my wife the other night, and we heard the chef of a restaurant in Florida say grilled amberjack was the house specialty. My wife asked what an amberjack was, and I told her it was a fish. She knew that, but she wanted to know what kind of fish an amberjack was.  This blog article is for her.

The greater amberjack is a large predatory fish found in warm ocean waters around the world.  They swim in schools located 60-200 feet deep, but they prefer coastal waters studded with manmade and natural structures such as shipwrecks and rocky outcrops.  Amberjack migrate to those structures to spawn, so their small offspring can hide in the crevices from larger fish.  Greater amberjacks reach a length of 6 feet long and can weigh up to 40 pounds, and they prey upon fish, squid and crustaceans.  During summer they expand their range north, and some populations migrate toward shore.

Greater amberjack.

Greater Amberjack range map. They prefer deep waters near the coast.

As far as I can determine, not a single fossil specimen of amberjack has ever been found.  None are listed on the paleobiology database.  However, amberjack are a deep water fish and potential fossil locations are likely inaccessible.  Amberjacks belong to the Carangidae family which includes jacks and pompano, and they’ve existed for millions of years.  Genetic evidence suggests amberjacks from the Atlantic colonized the Mediterranean Sea during the Late Pleistocene after an existing population there had already split into 2 clades.  The population of amberjacks in the North Atlantic recently diverged from the population in the Gulf of Mexico.  Closure of the ancient Tethys Sea, and the rise of the Isthmus of Panama caused speciation in the Seriola genus.

Grilled amberjack. Some specimens of amberjack can be toxic.

Amberjack living in tropical waters can accumulate toxins in their flesh by eating smaller reef fish that have been exposed to dinoflagellates responsible for red tides. 

Fish is my favorite food to charcoal grill.  I think fish flesh absorbs the charcoal grill flavor better than any other protein.

References:

Bobie T. ; et. al.

“Two Seas, Two Lineages: How Genetic Diversity is structured in Atlantic and Mediterranean Greater Amberjack Seriola dumerili: Russ 1810 (Perciformis, Carangidae)”

Fisheries Research

Swart, Belinda

“The Evolutionary History of the Genus Seriola, the Phylogeography and Genetic Diversity of S. Lalandi (Yellowtail) Across its Distribution Range”

PHD Thesis Stellenbosch University 2014

Yellow Autumn Wildflowers in my Neighborhood

My neighborhood is on the top of a fall line hill in a sandy soil zone. The sandy substrate originated during the Eocene (55 million – 33 million years ago) when this region was a sea shore. It is a narrow zone found across 6 states, and it borders the oak-hickory-pine forest to the north and the open pine savannah zone to the south. The original dominant trees in this zone were sand laurel oak and longleaf pine, but the latter has been replaced by loblolly pine which is faster growing and less dependent upon frequent fire. Before European settlement the region was subject to periodic grass fires that thermally pruned the open woodland. Today, fire suppression results in thick growths of oak saplings on vacant lots. The original environment likely consisted of widely spaced pine and oak with an abundance of herb and grass species growing in the sunny undergrowth. The name of my road is “Piney Grove,” indicating what this area looked like about 50 years ago when the road was first paved.

This time of year 3 common yellow flowers bloom in my neighborhood, and there were probably acres of them here before it was subdivided into lots and landscaped with non-native turf grasses. Cottony goldenaster (Chrysopsis gossypinus) is a tough plant well adapted for growing in hot sunny conditions with sandy soils. I assume the name is based on the appearance of the bud before the flower blooms–it resembles an unopened cotton ball. I could find just 1 scientific study of this plant, and it focuses on anatomical distinctions between this and similar species. I’ve noticed 1 species of bee, 1 species of butterfly, and a small hornet, pollinating this perennial. This species has probably occurred in this region for millions of years because it has had similar climate and soil for ages.

I have a natural patch of cottony goldenaster in my yard. I don’t have to spend money on flowers.

Common sulphur butterfly (Colias philodice) pollinating a cottony goldenaster flower. The fall brood of this butterfly is greenish-yellow and they look like a leaf. They feed upon clover during their larval stage.

I don’t know what species of bee this is. But it is also pollinating a cottony goldenaster.

Sticktights (Bidens sp.), also known as beggar-ticks, produce a zoochorus fruit. The fruit sticks to fur, feathers, and clothing, and the seeds are spread throughout the environment in this way. It’s impossible for a deer, fox, or human to walk through a field and not inadvertently collect many of these fruits. 150-200 species of sticktights exist.

Fruit of the sticktight. These fruits stay on the plant after it dies and this increases the chances for the seeds to be spread by passing animals.

There are even more species of hawkweeds (Hieraciums sp.). Botanists count over 10,0000 species of hawkweed. I think the species in my neighborhood is field hawkweed (H. aespotosum), but I am no botanical expert and I don’t even know of a source with all 10,000 species illustrated, described, and compared.

Hawkweed.