PALEONTOLOGY
New species of 65 million year old fossil shark discovered in Alabama, USA
This shark was one of the ocean’s top predators after the extinction of the dinosaurs
Peer-Reviewed PublicationIMAGE:
PALAEOHYPOTODUS BIZZOCOI TEETH.
view moreCREDIT: EBERSOLE ET AL.
Birmingham, AL (February 7, 2024) – Today, a team of scientists is pleased to announce the discovery of a new fossil shark species from Alabama, USA. The team is led by Jun Ebersole, Director of Collections, McWane Science Center, Birmingham, AL, David Cicimurri, Curator of Natural History, South Carolina State Museum in Columbia, and T. Lynn Harrell, Jr., Paleontologist and Fossil Collections Curator at the Geological Survey of Alabama in Tuscaloosa.
The shark is a new species of Palaeohypotodus (pronounced pale-ee-oh-hype-oh-toe-duss), which means “ancient small-eared tooth,” in reference to the small needle-like fangs present on the sides of the teeth. It has been named Palaeohypotodus bizzocoi, for the late Dr. Bruce Bizzoco (1949-2022) of Birmingham, AL. Bizzoco served as a Dean at Shelton State Community College, archaeologist, and was a longtime volunteer at McWane Science Center. The naming of this species honors Dr. Bizzoco’s lifelong commitments to education and the preservation of Alabama’s history.
According to Ebersole, the discovery of this shark was accidental.
“A few years ago, I was looking through the historical fossil collections at the Geological Survey in Alabama and came across a small box of shark teeth that were collected over 100 years ago in Wilcox County,” Ebersole said. “Having documented hundreds of fossil fish species over the last decade, I found it puzzling that these teeth were from a shark that I didn’t recognize.” Ebersole quickly realized that these teeth belonged to a new species.
“Perhaps one of the coolest aspects of this shark, is when it lived – the Paleocene, approximately 65-million-years-ago,” Cicimurri said. This is the time-period from just after the death of the dinosaurs, where over 75% of life on Earth went extinct.”
According to Cicimurri, this shark was a leading predator during the time when the oceans were recovering.
In Alabama, much of the southern half of the state was covered by a shallow tropical to sub- tropical ocean during the Paleocene. “This time period is understudied, which makes the discovery of this new shark species that much more significant,” Harrell said.
“Shark discoveries like this one give us tremendous insights into how ocean life recovers after major extinction events and also allows us to potentially forecast how global events, like climate change, affect marine life today,” Harrell continued.
As part of their study of this ancient shark, the team compared the fossil teeth to those of various living sharks, like Great Whites and Makos. According to Cicimurri, shark teeth differ in shape depending on where they are located in the mouth.
“By studying the jaws and teeth of living sharks, it allowed us to reconstruct the dentition of this ancient species and showed that it had a tooth arrangement that differed from any living shark,” Cicimurri said.
The naming of this shark is part of an ongoing project led by Ebersole and Cicimurri to document Alabama’s fossil fishes. Together, they have confirmed over 400 unique species of fossil sharks and bony fishes, which, according to Ebersole makes Alabama one of the richest places in the world in terms of fossil fish diversity.
The study, titled A new species Palaeohypotodus Glickman, 1964 (Chondrichthyes, Lamniformes) from the lower Paleocene (Danian) Porters Creek Formation, Wilcox County, Alabama, USA, was published today in the open access journal Fossil Record and can be downloaded here: htps://doi.org/10.3897/fr.27.e112800
About McWane Science Center
McWane Science Center is a nonprofit 501 (c)(3) science center, children’s museum, natural history museum, aquarium, and IMAX Dome Theater. Designed to “spark wonder and curiosity about our world through hands-on science,” McWane Science Center has welcomed millions of visitors since opening its doors in 1998. The McWane Collection houses one of the largest collection of fossils in the state of Alabama. For more information, visit www.mcwane.org.
Palaeohypotodus bizzocoi tooth.
CREDIT
McWane Science Center.
Modern day sand tiger shark.
CREDIT
Wikimedia commons
Photograph of the late Dr. Bruce Bizzoco (1949-2022), for whom the new species is named.
CREDIT
McWane Science Center.
ARTICLE TITLE
A new species of Palaeohypotodus Glückman, 1964 (Chondrichthyes, Lamniformes) from the lower Paleocene (Danian) Porters Creek Formation, Wilcox County, Alabama, USA
ARTICLE PUBLICATION DATE
7-Feb-2024
Dinosaurs’ success helped by specialized stance and gait, study finds
IMAGE:
EVOLUTIONARY TREE SHOWING HOW DINOSAUR LIMB ADAPTATION EXPANDED THROUGH THE TRIASSIC PERIOD UNTIL IT WAS GREATER OVERALL THAN THE SPREAD OF LOCOMOTION TYPES IN THEIR COMPETITORS, INCLUDING PSEUDOSUCHIANS, OTHER AVEMETATARSALIANS, AND OTHER ARCHOSAURS. THESE CHANGES ALSO INCLUDED MANY EARLY DINOSAURS WITH STRONG ADAPTATIONS TO CURSORIALITY (RUNNING). MASS EXTINCTIONS ARE MARKED ALONG THE TIME SCALE: PTME, PERMIAN-TRIASSIC MASS EXTINCTION; CPE, CARNIAN PLUVIAL EPISODE; ETME, END-TRIASSIC MASS EXTINCTION).
view moreCREDIT: AMY SHIPLEY
Dinosaurs’ range of locomotion made them incredibly adaptable, University of Bristol researchers have found.
In a new study, published today in Royal Society Open Science, findings show that the first dinosaurs were simply faster and more dynamic than their competitors and why they were able to dominate the Earth for 160 million years.
The researchers compared the limb proportions of a broad array of reptiles from the Triassic, the period of time from 252 to 201 million years ago, when dinosaurs first appeared and rose to prominence. They identified which of these ancient beasts was quadrupedal (four-footed) or bipedal (two-footed), and also looked at their cursoriality index, a measure of their running ability.
They found that, from the beginning, not only were the dinosaurs and their close relatives bipedal and cursorial – which meant they had limbs adapted for running, they also showed a much wider range of running styles than some of their close competitors, called the Pseudosuchia.
The pseudosuchians included the ancestors of modern crocodiles. Some were small insect-eating bipeds, but most were medium-to-large-sized carnivores and herbivores and they were diverse throughout the Triassic. The team found that dinosaurs and their kin, the Avemetatarsalia, maintained a higher range of locomotory modes throughout this period.
MSc Palaeobiology student Amy Shipley led the study. She said: “When the crunch came, 233 million years ago, dinosaurs won out.
“At that time, climates went from wet to dry, and there was severe pressure for food. Somehow the dinosaurs, which had been around in low numbers already for 20 million years, took off and the pseudosuchians did not.
“It’s likely the early dinosaurs were good at water conservation, as many modern reptiles and birds are today. But our evidence shows that their greater adaptability in walking and running played a key part.”
“After the end of the Triassic, when there was a mass extinction, the dinosaurs expanded again,” said Professor Mike Benton. “Most of the pseudosuchians were wiped out by the mass extinction, except for the ancestors of crocodiles, and we found that these surviving dinosaurs expanded their range of locomotion again, taking over many of the empty niches.”
Co-author Dr Armin Elsler explained: “When we looked at evolutionary rates, we found that in fact dinosaurs were not evolving particularly fast.
“This was a surprise because we expected to see fast evolution in avemetatarsalians and slower evolution in pseudosuchians. What this means is that the locomotion style of dinosaurs was advantageous to them, but it was not an engine of intense evolutionary selection. In other words, when crises happened, they were well placed to take advantage of opportunities after the crisis.”
“We always think of dinosaurs as huge and lumbering,” says Dr Tom Stubbs, another collaborator. “This reminds us that actually the dinosaurs started as nippy little insect-eaters.
“The first dinosaurs were only a metre long, up high on their legs, and bipedal. Their leg posture meant they could move fast and catch their prey while escaping larger predators.”
Co-author Dr Suresh Singh concluded: “And of course, their diversity of posture and focus on fast running meant that dinosaurs could diversify when they had the chance.
“After the end-Triassic mass extinction, we get truly huge dinosaurs, over ten metres long, some with armour, many quadrupedal, but many still bipedal like their ancestors. The diversity of their posture and gait meant they were immensely adaptable, and this ensured strong success on Earth for so long.”
Evolution of the thigh bone (femur) through the Triassic, starting with a very limited array of shapes, and ending with a broad array of shapes for the dinosaur femur (high disparity), indicating a wide range of locomotion modes.
CREDIT
Amy Shipley
The paper:
‘Locomotion and the early Mesozoic success of Archosauromorpha’ by AE Shipley, A Elsler, SA Singh, TL Stubbs and MJ Benton in Royal Society Open Science.
JOURNAL
Royal Society Open Science
METHOD OF RESEARCH
Computational simulation/modeling
SUBJECT OF RESEARCH
Animals
ARTICLE TITLE
Locomotion and the early Mesozoic success of Archosauromorpha
ARTICLE PUBLICATION DATE
7-Feb-2024
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