Snowy Winters and Dry Summers Prevailed in Southwestern North America during the Late Pleistocene

Ice Age climates spawned dramatically altered weather patterns compared to those of the present day. The result of those different weather patterns is evident in how changed Southwestern North America has become since then. During Ice Ages Southwestern North America was a land of vast lakes, abundant springs, and widespread wetlands. There even was a lake in Death Valley, California where it almost never rains today. There were especially large lakes in Utah, Nevada, and central Oregon–areas that today are quite arid. Scientists debate the source of the greater precipitation that occurred then. Some think the source was summer rains coming from fronts originating in the tropics, while most believe the polar jet stream carried moisture from the North Pacific that fell as heavy snows during winter. A new study of carbon and oxygen isotope ratios in tooth enamel from Pleistocene mammals supports the latter scenario.

Scientists analyzed 39 teeth from mammoth, bison, horse, and camel excavated from the Tule Spring Fossil Bed National Monument in Nevada. They can determine how precipitation was delivered based on the ratios of carbon and oxygen isotopes in the teeth because the animals ate the plants that absorbed the water, and the animals directly drank it. Most of the precipitation in the region came from heavy snows, and the lakes refilled every spring and early summer from snow melt. They believe summers were relatively dry, and lakes began to evaporate until seasonal snowfall. Mammoths, bison, and horses ate a lot of the fresh grass that grew tall on water from snowmelt. Horses may have eaten more grass here during Ice Ages than they do today. But camels browsed on saltbush (Atriplex sp.). The presence of this species indicates dry summers and arid localities within the lush landscape. Scientists think glaciers to the north of the region split the polar jet stream, and the lower stream carried moisture from the North Pacific, causing winter precipitation. Lake levels were highest during the Last Glacial Maximum following Heinrich Events that occurred when ice dams melted, and massive pulses of freshwater studded with ice bergs flooded into the oceans. Moisture in earth’s atmosphere increased following Heinrich events.

Map of Southwestern North America during the Late Pleistocene. Meltwater from much snowier winters caused the formation of giant lakes in the region then. From the below reference by Munroe and Laabs.

Beth Zaiken’s depiction of wildlife in Nevada during the last Ice Age. Vegetation was much lusher than it is today due to higher annual precipitation.

When glaciers retreated at the end of the Ice Age, the polar jet stream recombined and began to flow to the north. Winter snowfall was greatly reduced, and the lakes gradually evaporated. The Great Salt Lake of Utah is a remnant of a much larger freshwater lake that existed during Ice Ages.

The abundant wetlands and lakes of the region hosted many species of birds that today breed in the Arctic during summer. These species could not live in the Arctic during the Ice Ages because their present-day ranges were under miles of glacial ice. Their breeding ranges shifted to the Southwest. See also:

https://markgelbart.wordpress.com/2017/04/09/ice-age-western-lakes-and-altered-bird-migrations/

References:

Kohn, M. et. al.

“Seasonality of Precipitation in the Southwestern U.S. during the Late Pleistocene Inferred from Stable Isotopes in Herbivore Tooth Enamel”

Quaternary Science Review 290 November 2022

Munroe, J.; and B. Laabs

“Temporal Correspondence Between Pluvial Lake High Stands in Southwestern U.S. and Heinrich Event 1”

Journal of Quaternary Science 28 (11) 2013

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The Early-Mid Pleistocene European Jaguar (Panthera gombaszoegensis) was not Actually a Jaguar

During 1938 M. Kretzoi, a paleontologist, studied some unidentified lower fossil teeth and concluded they belonged to an extinct species of jaguar that roamed Europe during the early to mid-Pleistocene. He gave the species the scientific name Panthera gombaszoegensis. Paleontologists long thought this species was ancestral to the American jaguar (P. onca) and some thought it was the same species. A mostly complete skull was finally found in a Belgian sinkhole (the La Belle-Roche fossil site) during 1980, but paleontologists didn’t really study it until recently. They compared this fossil skull with those from extant species of cats in the Panthera genus including lion, leopard, tiger, jaguar, and snow leopard. They concluded P. gombaszoegensis was not a jaguar after all, though the lower teeth were similar. Instead, this species was most closely related to the tiger (P. tigris) and based on the characteristics of the skull they believe it was a sister species to the tiger, having diverged directly from the same common ancestor. This makes sense geographically because its range was much closer to the tiger than the jaguar. P. gombaszoegensis lived from 2 million years BP to 350,000 years BP, and it is thought to have been a generalist predator, taking whatever prey species they could bring down. Lions and leopards expanded their ranges into Europe from Africa about 350,000 years ago and likely ecologically replaced P. gombaszoegensis.

Map showing range of modern tigers, modern jaguars, and the extinct Panthera gombaszoegensis. An anatomical comparison concludes European jaguars were more closely related to modern tigers than jaguars. This makes more sense geographically. The lower image is a map showing fossil localities where this species has been found in Belgium. Image from the below reference.

Skull of Panthera gombaszoegensis. A comparison of this skull with extant species of cats in the Panthera genus suggest it is a sister species of modern tigers, not jaguars. Image also from the below reference.

Paleontologists think the Panthera genus originated in central Asia about 6 million years ago during the late Miocene. The direct ancestor of the jaguar is unknown. The oldest jaguar fossil known was found in a cave in West Virginia and dates to 850,000 years ago. It descended from a species that crossed the Bering land bridge sometime during the early Pleistocene.

Reference:

Chator, N.; M, Michaud, and V. Fischer

“Not a Jaguar After All: Phylogenetic Affinities and Morphology of the Pleistocene Felid Panthera gombaszoegensis“

Papers in Paleontology 2022

link https://www.researchgate.net/publication/363739515_Not_a_jaguar_after_all_Phylogenetic_affinities_and_morphology_of_the_Pleistocene_felid_Panthera_gombaszoegensis

A Genetic Study of Mark Gelbart–My 23 and Me Results

My late mother’s cousin researched our family genealogy years ago. and I know quite a bit about our family’s history. Nevertheless, I wanted to know more. I wanted to know what the science reveals. I submitted my DNA to 23 and Me, a service that analyzes a person’s genetics for a fee. The results arrived a few days ago. They determined I was 51.2% British (English and Irish) and 48.8% Ashkenazi Jew. I must have inherited a little more DNA from my mom than from my dad. I already knew I was half of English descent and half Jewish. My mom’s cousin’s genealogy chart on my maternal side goes back 1000 years. Most of the names on my maternal side are very English–Parsons, Penhollow, Howe, etc. However, the oldest names are Norman (the French speaking Vikings who invaded England 1000 years ago). I have no Scandinavian ancestry according to these results. 23 and Me must interpret British ancestry as the indigenous British population + Viking invaders + the Germanic tribes who invaded England even earlier. I also take issue with 23 and Me’s classification of Ashkenazi Jews as European. Ashkenazi Jews originated in the Middle East (primarily the location of modern Israel). They are descendants of the people Romans conquered and forcibly removed from Judea 1900 years ago. The foundling population of Ashkenazi Jews was likely just a few hundred individuals who clung to their traditions. The rest were assimilated or perished.

I have good knowledge of my ancestry, so the results were not a surprise. I’m half British and half Ashkenazi Jew. I take issue though with 23 and Me classifying Ashkenazi as European rather than Middle Eastern. Ashkenazi Jews originated in the Levant.

I was most interested in finding out if I had any relatives I didn’t know about. I found out I have seven 2nd cousins and hundreds of 3rd and 4th cousins who submitted their DNA to 23 and Me. I don’t know any of them. My closest relative who submitted their DNA to 23 and Me supposedly shares a Great Grandparent with me. I know the surnames of 7 out of 8 of my Great Grandparents. They are Gelbart, Shneier, Klarriech, Bailey, Wages, Cobb, and Parsons. The family tree provided by 23 and Me suggests she is related to a Great Grandparent on my Jewish side, but I can’t determine who. She is 1/4th Jewish and 1/4th English. This result is a bit of a mystery, and I think this result might be slightly off. I think it is more likely we share a Great-Great Grandparent, probably from the Klarriech side. I think there was someone from that side who arrived in the U.S. early enough. Her mother was born in 1930. My 2nd closest relative shares a Great-Great-Grandparent, and I think I did figure this one out. He includes the Bailey surname in his list of family surnames. Sam Bailey lived from 1840-1922, and he is one of my Great-Great-Grandparents. I’ve lost touch with my mom’s paternal side relatives, even though many of them live here in Georgia. My Grandfather called one side of his family a “rough bunch” and “horse thieves from Alabama.” I’d be interested in meeting their descendants. I thought I wouldn’t have many Jewish relatives because of the Holocaust, but I was wrong. There are lots of Jewish-sounding names on my paternal side. The list of places where their parents were born is like a map of where Ashkenazi Jews ranged. Birthplaces listed by my 23 and Me relatives include U.S. (359), Poland (217), Russia (193), Ukraine (167), Romania (71), Hungary (67), Lithuania (67), Austria (61), Germany (61), Belarus (59), U.K. (37), Canada (28), Latvia (20), Czeck Republic (11), South Africa (10), Moldavia (10), Italy (9), Israel (7), France (7), and the Netherlands (5).

23 and Me also estimates the chances of certain traits. I do prefer salty snacks over sweet. They gave that a 57% chance. Against the odds, I do like broccoli and Brussel sprouts and cilantro. Unfortunately, also against the odds I have a bald spot and back hair.

I do have back hair and a bald spot, so that is against the odds, but I don’t have dimples.

I do have blue eyes. My hair thinning didn’t occur until after 40.

23 and Me goes way back and can tell which haplogroup I belong to. My mom is from maternal haplogroup H1 which originated from one woman who lived 18,000 years ago and spread throughout Europe and Asia after the Last Glacial Maximum. My paternal haplogroup is much older originating 47,500 years ago in North Africa. They are known as haplogroup E-M5021. They eventually became farmers. The report also claims I’m less than 2% Neanderthal, but I am more Neanderthal than 76% of the population.

My maternal line is haplogroup H1 which originated about 18,000 years ago. We all descend from the same mother who lived in Africa between 150,000-200,000 years BP.

My paternal haplogroup is E-M5021. They are thought to have become farmers.

I was glad I submitted my DNA results, and I hope more of my relatives eventually submit theirs.

Pleistocene Howls

Hyoid bones are rarely found in most fossil sites. Canid hyoid bones are a collection of 9 small bones held together with ligaments. The hyoid bone supports the pharynx, larynx, and tongue. During the process of decomposition after an animal dies, the larger bones are more likely to be preserved, but the small bones such as the ones that make up the hyoid get separated and oftentimes crushed. They then dissolve or are broken into unrecognizable fragments. However, the La Brea tar pits are an exceptional fossil site with excellent preservation, and many complete hyoid bones have been found there. Scientists recently studied the canid hyoid bones found there and compared them to the hyoid bones found in extant species of coyotes and wolves.

Diagram of a dire wolf hyoid bone from the below reference.

Illustration by Mauricio Anton. During the Pleistocene big cats mostly hunted in forested areas while dire wolves mostly hunted in open areas.

Dire wolves had larger hyoid bones than modern species of wolves including gray and red wolves and coyotes. They howled with a lower frequency and deeper pitch than any species of extant American wolf. Scientists couldn’t find any difference between the hyoid bones of coyotes and red wolves. Pleistocene coyotes were larger than modern coyotes and so were their hyoid bones. They howled with a lower frequency and deeper pitch than modern coyotes. If we could hear a dire wolf howl, we would definitely notice a much deeper howl than normally heard today by people lucky enough to live where wolves and coyotes’ howl.

Reference:

Flores, D., E. Eldridge, E. Eliminowski, E. Dickinson, A. Hartstone-Rose

“The Howl of Rancho La Brea: Comparative anatomy of Modern and Fossil Canid Hyoid Bones”

Journal of Morphology April 2020

https://www.researchgate.net/publication/340726915_The_howl_of_Rancho_La_Brea_Comparative_anatomy_of_modern_and_fossil_canid_hyoid_bones