Wooster’s Fossils of the Week: A foraminiferal ooze from the Pleistocene of Italy

August 18th, 2013

YCM forams 1On a recent field trip to Sicily, our paleontological party visited outcrops at Cala Sant’Antonino on the western side of the Milazzo Peninsula in the northwestern part of the island. We saw there an Early Pleistocene sedimentary unit informally called the “Yellow Calcareous Marls”. With a handlens you would see a close view of the rock like the image above. It consists almost entirely of tiny hollow white spheres with occasional dark flecks. In the lab back home these little calcitic balls were revealed to be tests (skeletons) of foraminiferans known as Globorotalia inflata (d’Orbigny, 1839). This is a classic example of a biogenic sediment called foraminiferal ooze, samples of which are now in Wooster’s paleontological and sedimentological teaching collections.
Foram-Marl-060913This is the outcrop of the “Yellow Calcareous Marls” at Cala Sant’Antonino from which the above samples were collected. The rock is very soft and powdery to the touch.

YCM forams 2In this closer view of the rock the individual foraminiferal tests are more apparent. Near the center is one example showing the connected bulbous chambers (making it multilocular) and the slit-like aperture between them. These tests are slightly recrystallized, giving them a sugary look. The dark bits are sand-sized volcaniclastic grains derived from early eruptions of the Mount Etna complex.

Globorotalia_inflataThese are modern examples of Globorotalia inflata. (The scale bars are 0.1 mm.) The bumpy surface texture, bulbous chambers and distinctive aperture make identification of the fossil examples fairly easy. The images were taken by Bruce Hayward.

Globorotalia inflata is a long-lived planktonic species, meaning it floats about near the top of the water column throughout the oceans. In life these single-celled organisms extend thin strands of material (pseudopodia) into the water around them to collect organic material and the occasional diatom or radiolarian for nutrition. They live in populations with billions of individuals, so under the right conditions their tests can accumulate on the seafloor in numbers so vast they form thick deposits, our foraminiferal oozes. Our particular ooze in this story formed in relatively deep (epibathyal), cool waters during one of the early glacial intervals. This foraminiferan turns out to be a critical guide to the age of the unit as well as its paleoenvironmental context.


Fois, E. 1990. Stratigraphy and palaeogeography of the Capo Milazzo area (NE Sicily, Italy): clues to the evolution of the southern margin of the Tyrrhenian Basin during the Neogene. Palaeogeography, Palaeoclimatology, Palaeoecology 78: 87–108.

Sciuto, F. 2012. Bythocythere solisdeus n. sp. and Cytheropteron eleonorae n. sp. (Crustacea, Ostracoda) from the Early Pleistocene bathyal sediments of Cape Milazzo (NE, Sicily). Geosciences 2012 2: 147-156.


Limestones, basalts, the wine-dark sea and the brooding volcano

June 16th, 2013

1.BasaltLimestone061613CATANIA, SICILY, ITALY–Today we had our last field trip associated with the 2013 International Bryozoology Conference. We traveled to the east coast of Sicily at Castelluccio, which is south of Catania and north of Syracuse. The weather could not have been better. It was, as a commenter has said, “impossibly beautiful”.

The view above is of Early Pleistocene limestones resting on tholeitic basalt flows. As our guides said, in this place we could see the interplay of extensional tectonics, regional uplift, and glacially-controlled sea-level changes. The visuals were stunning. In the background you can see the east flank of Mount Etna.
2.Thalassinoides061613The limestones were of shallow-water origin and very diverse. One layer was almost completed bioturbated (biologically stirred up) by crustaceans, producing a trace fossil of connected tunnels called Thalassinoides.
3.FossilScallops061613Fossils were abundant in some units. Here is an horizon rich in scallop shells. These shells are often preferentially preserved because they are made of hardy calcite rather than chemically unstable aragonite like most other mollusk skeletons.
5.Dike061613The interactions between the basalt flows and the calcareous sediments were fascinated. Above you see a black basaltic dike cutting vertically through the limestones. Why there are no visible baked zones is a mystery to me.
4.BakedZone061613In this image we have basalt above and sediments below. The pink color of the limestones tells us they were cooked by the hot lava that flowed over them.
6.Beachrock061613There are a variety of post-depositional geological processes operating at this outcrop. One of them is the superimposition of beachrock during sea-level highstands. Beachrock is a cemented sediment formed in the surf zone by precipitation of carbonate. This particular beachrock was plastered onto an eroded limestone cliff like stucco. You can see black basalt among the diverse clasts.
7.EtnaBayView061613Over it all rules Mount Etna, here viewed from the top of the outcrop. It was unusually smoky today, which does not show well in our photographs because of the murky haze. We headed to this behemoth for the second and last stop of our field trip.

A shelly bonanza from the Pleistocene of Sicily

June 5th, 2013

5. MegaraDitch060513NOTO, SICILY, ITALY–Our second stop of the day on this International Bryozoology Association field trip was in an unimpressive ditch (above) near Megara. But, of course, there is paleontological gold here: an assemblage of extremely well-preserved marine fossils.

6. AndrejMegara060513Colleague Andrej Ernst is examining a layer of shells extending the length of the drainage ditch.

7. SerpulidsMegara060513Her are some beautiful pectinid bivalves (scallops) with the treat for me: abundant serpulid worm tubes. There is an extensive sclerobiont (hard substrate dwelling) community on these shells.

7a. TurritellidsMegara060513Turritellid gastropods (snails) are extremely common in this assemblage. Note that several of these specimens have small holes drilled in them by predatory gastropods. We found naticid gastropods here too, which were probably the culprits.

8. HornedQuadrupedsMegara060513This mother lode of fossils was guarded by a herd of horned beasts. This one had a bell on it, so I assumed it was the most dangerous and stayed far away. (Love this new zoom lens!)


Sicilian fossils at last!

June 4th, 2013

FieldStopOne060413CATANIA, SICILY, ITALY–After lunch our International Bryozoology Association field trip actually collected fossil bryozoans. We visited a quarry exposure of Lower Pleistocene cemented marls rich in the bryozoan Celleporaria palmata (Michelin), along with many other species. These were apparently from a thicket of bryozoan colonies broken up in a storm and deposited as a debris flow down slope. The location is south of Catania at Pianometa.

Celleraria060413Lower Pleistocene Celleporaria palmata fragments at Pianometa. This was a very rapid-growing, branching bryozoan colony easily fragmented by storm currents.

Volcaniclastic060413Below those bryozoan-loaded beds is this unusual sequence. The darker layered units are volcaniclastic sediments derived from early eruptions from the Mount Etna complex. Occasionally boulders would roll downslope and be deposited as xenoliths (“foreign rocks”) Later the cemented sediments cracked repeatedly due to the intense earthquake activity associated with this tectonic boundary between the European and African plates. Those cracks filled with marly sediment from above.

SheepCheeseFarm060413The last visit of the day was to a sheep cheese farm. One sheep produces about a liter of sheep’s milk. The cheese we sampled (some more than others) is very soft — like cottage cheese without the lumps, or a soft ricotta. Interesting (and unpasteurized). We watched four rams beat each other bloody in an ongoing context monitored by large black dogs. I suppose it is part of the herding process, grim as it is.

Products of an angry giant

June 4th, 2013

SicilyCyclopeanIslands060413CATANIA, SICILY, ITALY–They may look like impressive sea stacks to you, but it turns out these are three huge stones thrown by the aggrieved and wounded cyclops Polyphemus at Odysseus as he escaped that infernal cave. Who knew?

This morning we traveled north of Catania to the Ciclopi Marine Protected Area near Aci Castello and Aci Trezza to look at the evidence of the ancient volcanic activity that led to Mount Etna, and to snorkel and dive on the life-encrusted rocks in the blue, blue waters.

Island060413We took a boat ride all of about 300 meters across the bay to the tiny island of Lachea, shown above. Notice that there is a crack running through the rocks seen just above the boat. This is an active fault that runs through the middle of the island. Also note that there is a mix of light and dark rocks visible.

IslandBasalticIntrusion060413Lachea is a combination of whitish marls and claystones above with black basalt injected from below. This is the very beginning of volcanic activity in this region as hot magma began to work its way into the overlying sediments of a shallow sea. When the lava erupted onto the seafloor, masses of pillow basalts formed (see previous post). The cyclopean rocks in the top image are eroded roots of the massive basalt flows. They show beautiful columnar jointing.

Etnafromisland060413From Lachea we can see the glowering outline of Mount Etna, the true giant in our story.

StationSign060413The island of Lachea and its surrounding rocks has been the site of a research station for over a century. The fauna and flora of both the island and the seafloor down to 110 meters are protected by law.

IslandLizard585This pretty green lizard is common on Lachea and apparently endemic (found only there). It is Podarcis sicula ciclopica. Its mating season of three months is about to begin, so there was much lizardly activity.

Grotto060413One of the first places we visited on the island was this tiny historical grotto. Only five of us could crawl into this completely dark chamber at a time. Once inside you can carefully stand up and (at least some of us) touch your head on the ceiling. That turned out to be a mistake because the guiding biologists then show you the unique cave spiders hanging on their webs about your ears!

Lunch060413Finally I must show you at least one of our large Sicilians lunches, this one back in Catania after our morning marine excursion. We are eating well, if a bit later than usual — and with much more time in the process!


Wooster’s Fossil of the Week: Cast of a lower jawbone of the largest ape ever (Pleistocene, southern China)

March 17th, 2013

Gigantopithecus_blacki_mandible_010112The above is one of my favorite “fossils”, a commercially-available cast of the lower jawbone of Gigantopithecus blacki, a giant extinct ape. It was produced from an actual Pleistocene fossil found in a cave near Liucheng, Guangxi, in southern China. I like it especially because it is sometimes associated with the mythical “Bigfoot”.

Gigantopithecus blacki was the largest ape that ever lived: up to three meters tall and weighing over 500 kilograms. (G. blacki is known only from teeth and mandibles such as that shown above, so these size estimates are based on scaling.) It was a contemporary with early versions of our own species, which must have led to a few astounding encounters for our ancestors. G. blacki was two or three times heavier than the largest gorillas today.

Gigantopithecus blacki appears to have lived in bamboo forests. Striations on its teeth, and the occasional phytolith stuck in the enamel, shows that this species was a vegetarian. It may have even had a lifestyle much like today’s pandas.

The molars of Gigantopithecus blacki look surprisingly like ours with their multiple cusps and broad surfaces. This is the result of convergent evolution and not an indication of a recent common ancestry. (They are analogous features, not homologous.) G. blacki is now classified in the Subfamily Ponginae with their cousins the orangutans.

What is most fun about Gigantopithecus these days is its association with the “Bigfoot” illusion. Look at how seriously the people at the “Bigfoot Field Researchers Organization” take the possible connection of Gigantopithecus and Bigfoot. Despite their objections, we really can wonder why we’ve never found evidence of this giant ape in North America, including bones, teeth, legitimate footprints or real photographs. A living three-meter tall ape is a bit difficult for science to have missed! (Unless, of course, Bigfoot has supernatural powers.)


Coichon, R. 1991. The ape that was – Asian fossils reveal humanity’s giant cousin. Natural History 100: 54–62.

Ciochon, R., et al. 1996. Dated co-occurrence of Homo erectus and Gigantopithecus from Tham Khuyen Cave, Vietnam. Proceedings of the National Academy of Sciences of the United States of America 93: 3016–3020.

Jin, C., et al. 2009. A newly discovered Gigantopithecus fauna from Sanhe Cave, Chongzuo, Guangxi, South China. Chinese Science Bulletin 54: 788-797.

Wooster’s Fossil of the Week: A crab from the Pleistocene of northern Australia

November 18th, 2012

Isn’t this amazing preservation? This fossil crab, which we received as a donation a few years ago, is Macrophthalmus latreillei (Desmarest, 1822) from the Pleistocene of northern Australia. It is virtually identical to its modern counterpart of the same species, Latreille’s Sentinel Crab.

M. latreillei has large, stalked eyes. It likes to hide under a layer of sand with its eyes sticking out looking for predators. It is mostly active in the night, burrowing through the sediment collecting deposited organic material. It is found throughout the Indo-Pacific region.

The modern crab species M. latreillei was named in 1822 by the French zoologist Anselme Gaëtan Desmarest (1784–1838), shown above. He was a student of two other famous French scientists: Georges Cuvier and Alexandre Brongniart. He was the Professor of Zoology at the École nationale vétérinaire d’Alfort, succeeding the zoologist Pierre André Latreille (1762-1833), for whom he named this crab.
Latreille (above) was a most interesting fellow. He was an entomologist and a specialist in crustaceans. In 1786, when he was 24 years old, he was ordained a priest. This turned out, in hindsight, to be an almost fatal mistake. He was arrested by French revolutionaries in 1794 on suspicion of being a counter-revolutionary monarchist cleric (which he likely was). He was sentenced to deportation to a miserable tropical island prison. Just before he was scheduled to be shipped away, his jailers found him carefully studying a beetle crawling across his grungy cell floor. The authorities thought he had gone crazy in prison, but Latreille announced that the insect was a very rare species. This got back to an expert who confirmed the beetle as Necrobia ruficollis. Other experts then intervened to rescue the perceptive Latreille from prison and a tropical grave. To this day an image of this beetle is engraved on Latreille’s tombstone in Paris. Taxonomy saved a life.


Barnes, R.S.K. 1967. The Macrophthalminae of Australia, with a review of the evolution and morphological diversity of the type genus Macrophthalmus (Crustacea: Brachyura). Transactions of the Zoological Society of London 31: 195-262.

Dupuis, C. 1974. Pierre André Latreille  (1762-1833): the foremost entomologist of his time. Annual Review of Entomology 1974: 1-13.

Wooster’s Fossil of the Week: A mastodon tusk (Late Pleistocene of Holmes County, Ohio)

June 24th, 2012

This long and weathered tusk sits in a display case outside my office. It is from the American Mastodon (Mammut americanum) and was found many decades ago in Holmes County, just south of Wooster. A tooth found with it was a previous Fossil of the Week. Such tusks are rather rare because the ivory tends to disintegrate faster than tooth and bone. Our specimen is, in fact, hollow and held together by wires.
Above is a closer view of the proximal end of the tusk (the part closest to the face). You can see the hollowness and, curiously, that the ivory is charred. I used to tell students that the mastodon must have been hit by lightning, but I stopped when they took me too seriously!

This gives me a chance to mention a mastodon specimen I recently saw in a visit earlier this month to this famous place:
Monticello is, of course, the home of Thomas Jefferson, a Founding Father and the third president of the United States. Jefferson was a science enthusiast, and paleontology was one of his passions. He was fascinated with ancient life, and some have considered him the first American paleontologist. One room of the White House, for example, appears to have been devoted to his fossil bone collection.

Mastodons were particularly interesting to Jefferson because of an odd idea that was in vogue in France at the time. Georges-Louis Leclerc, Comte de Buffon, a famous French naturalist, wrote that “a niggardly sky and an unprolific land” caused life in the New World to be weak, small and degenerate. Life in North America was considered by the French to be quite inferior to that in Europe. Jefferson knew, of course, this was nuts. Having the bones of a North American elephant, as large or larger than any other elephants, would show the Frenchies how wrong they were. And Buffon eventually agreed, although he died before he could correct his books.
Above is a lower jawbone of Mammut americanum in Monticello. I wish I could have taken my own photograph, but this was not allowed. I’ve had to make do with one of their images online.

Curiously, Jefferson had one serious deficit when it comes to calling him a paleontologist. He apparently did not believe that species ever go extinct. When he dispatched Lewis and Clark on their expedition, for example, he expected them to find living mastodons deep in the American interior. Too bad they didn’t!


Conniff, R. 2010. Mammoths and Mastodons: All American Monsters. Smithsonian Magazine, April 2010.

Semonin, P. 2000. American Monster: How the Nation’s First Prehistoric Creature Became a Symbol of National Identity. New York University Press, New York, 502 pages.

Thomson, K.S. 2008. The Legacy of the Mastodon: the Golden Age of Fossils in America. New Haven, Connecticut, Yale University Press.

Wooster’s Fossil of the Week: a nestling bivalve (Pleistocene of The Bahamas)

April 22nd, 2012

This weathered and encrusted shell was pulled from a round hole bored in a Pleistocene reef (about 125,000 years old) exposed on San Salvador Island, The Bahamas. It is Coralliophaga coralliophaga (Gmelin 1791), a derived venerid bivalve (a type of heterodont, meaning that it has cardinal and lateral articulating teeth inside its valves.) I collected it back in 1991 while studying an inter-reef unconformity that recorded a drop and rise of sea level (Wilson et al., 1998; Thompson et al., 2011).

Coralliophaga means “coral eater”, which is a bit of a bum rap for this clam. It is found inside borings in coral, true enough, but those holes were drilled by some other types of clams. C. coralliophaga only occupies the holes after the original dweller is dead and gone (Morton, 1980). We call this kind of behavior “nestling“, which seems a polite way of saying “squatting”. These bivalves grew to adulthood in these cavities protected from most predators as they filtered the seawater for food.
The trace fossil Gastrochaenolites torpedo (the elongate borings) with a nestling (and broken) C. coralliophaga in the lower right corner.

The posterior ends of these shells are encrusted by a variety of calcareous algae and other organisms during life, so they look a bit rough on their outsides. Often the encrustations are so thick that the shells are difficult to extract from the holes, so getting a nice complete shell like the one at the top of this entry is rare.
C. coralliophaga was named by Johann Friedrich Gmelin (1748–1804) in 1791. Gmelin was an accomplished naturalist from Tübingen, Germany. He received an MD degree in 1769, with his father (Philipp Gmelin) as his advisor. He taught at Tübingen and the University of Göttingen, writing many textbooks in fields from chemistry through botany. He published the 13th edition of Systema Naturae by Carolus Linnaeus, inserting his new taxa in the text, including our new friend Coralliophaga coralliophaga.


Gmelin, J.F. 1791, in Linnaeus, C. Systema Naturae per Regna Tria Naturae, Secundum Classes, Ordines, Genera, Species, cum Characteribus, Differentiis, Synonymis, Locis. 13th Edition, Lyon : J.B. Delamolliere Tom.

Morton, B. 1980. Some aspects of the biology and functional morphology of Coralliophaga (Coralliophaga) coralliophaga (Gmelin, 1791) (Bivalvia: Arcticacea): a coral-associated nestler in Hong Kong. pp. 311-330, in: Morton, B., The Malacofauna of Hong Kong and southern China. Proceedings of the First International Workshop on the Malacofauna of Hong Kong and Southern China, Hong Kong, 1977. Hong Kong: Hong Kong University Press.

Thompson, W.G., Curran, H.A., Wilson, M.A. and White, B. 2011. Sea-level oscillations during the Last Interglacial highstand recorded by Bahamas corals. Nature Geoscience 4: 684–687.

Wilson, M.A., Curran, H.A. and White, B. 1998. Paleontological evidence of a brief global sea-level event during the last interglacial. Lethaia 31: 241-250.

Sand and Gravel in the Holmesville Moraine

April 13th, 2012

The College of Wooster Geomorphology class set out to explore the Holmesville Moraine, a 20 minute drive south of Wooster straight down the Killbuck River Valley. It was a beautiful day, except for the rain. The first stop was Holmesville Sand and Gravel, a company which mines and sorts the deposit and sells it for various building and homeowner applications. We ended up classifying this as a Kame Moraine as most of the sediment is sand and gravel intermixed with diamict all piled up into a great cross valley ridge. This is likely the dam for Glacial Lake Killbuck, which was impounded to the north.

The Separator – This machine and associated conveyors sorts the gravel from the sand from the silt.

Sorted piles – note the varying angles of repose.














The dredge sucks sand from 70 feet down in this lake. It is then piped to the Separator.


Fine-grained sand and silt is returned to the lake – note the delta. A wave-dominated delta that is revealed with a modest drop in lake level.

Continue reading this post to see why the group is dumbfounded.

Ice-contact stratified drift – sediments range from diamicts to stratified sands and gravels. Many of the gravels are cemented. Note that the lower left is a bedrock contact. This is the guts of the kame moraine.

Cemented sand and gravel – note the evenly-space joints where the rivelets have excavated the materials – joints from unloading?

Cemented and partially stratified diamict – this unit is a major challenge to remove in mining.

Raindrop imprints on mudcracks.

Ditch draining the floor of former Glacial Lake Craigton – note the peaty sediments and the tiles. Note the meandering thalweg within the ditch.

« Prev - Next »