Welcome to the Flatwoods Conservation Park
This EC might be a bit daunting at first glance but if you choose to complete it , you will see some interesting Florida Fossil Shells and get some excercise to boot. The trail itself is a 7.5 mile loop that you can take on in several ways. Those include on a bike, walking or with inline skates ( I've seen many folks out here doing just that) . If you choose to bike the route IS only ONE-WAY. Please follow the arrows. The park is open daily from 8am to 6pm and there is a $2 charge for parking. Please bring plenty of water. There will be no need to venture into any swampy areas . All of the examples are provided on the shoulders of the main paved trail.
Leashed dogs are permitted except where posted. Drones and other remote controlled vehicles are not permitted in the preserve.
More information about the park can be found here: Flatwoods Park | Lower Hillsborough Wilderness – Florida Hikes
I have walked and ridden this route many times and have always been facinated by the different shells I saw. The last several trips I took a deeper observation and began doing some research. Come to find out the shells are not from Hillsborough County but instead have been brought in from Hendry County. What's really interesting is that at each waypoint (1-8) there is a specific Fossil Shell that is the dominate one there. It's like different piles of each type were dumped there purposely but in actuality as they were mined at the Cochran Shell Pit in Hendry County and brought here from each level of the quarry they had been taken from. Millions of years on display here, each level of the Shell Pit showing what was present during that era.
Below you will learn about several different shells all of which are extinct and fossils from Hendry County . You will see all of these along your journey. Your task will be to identify which one you find at the given waypoints
Under natural light, fossilized seashells often appear devoid of color. Like you will find mostly here, Their hues may have faded over millions of years, leaving them pale and neutral in appearance.
However, there’s an intriguing twist! When exposed to ultraviolet (UV) light, these shells reveal hidden patterns and take on a bluish glow. This fluorescence hints at the presence of dark pigments that were once part of their original colors. By reversing the UV images, scientists can infer what these shells might have looked like in their vibrant past.
Some background of these Florida Fossil Shells
25 million years ago is when Florida started emerging from the sea. The land didn't just pop-up and stay in the light. The process had it coming up and resubmerging many times and when this occured it produced some interesting mixing of fossil types. Sea creatures as well as small land animals are often found bunched together. This all happened during the Pleistocene period. So 12 million year old seashells can be discovered along creekbeds in many Florida Counties such as Calhoun, whereas the ones placed here from Hendry County ( south central Florida) are in the 3-5 million year old range. The limestone in those areas of Central Florida have helped preserve and protect these ancient relics of the sea.The quarry where these were brought from is a great example of that.
How are Sea Fossils Formed?
Seashell fossils are formed when a sea animal with a shell dies, and their body and shell begin to decompose. Seashell fossils are more common than other fossils because the shell is hard and therefore more likely to be preserved, compared to organisms with only soft tissue. Animals without a shell or bones hardly ever become fossilized. These remains are often captured in sediment (which eventually forms sedimentary rock) or other mineral mediums. The calcium carbonate composition of seashells means they are predisposed to fossilize easily, as the shell is simply preserved along with the surrounding rock.
From Sciencing.Com we find :
Molds and Casts
Molds and casts are other types of body fossils. A mold is an imprint left by the shell of a hard skeleton on surrounding rock, such as dinosaur bones buried beneath many layers of sediment. A mold may be internal or external. An internal mold is on the underside of shell left on the surface of rock that formed when sand or mud filled the inside of the shell. An external mold is on the outside of the shell. Whenever a shell or bone breaks out of rock, it leaves an external mold behind.
Replicas of molds are known as casts, which may be produced naturally when the space left behind after mold removal fills with sediment. Paleontologists can also produce casts from molds with latex rubber or modeling clay to learn more about fossils.
Permineralization and Petrification Fossils
When groundwater saturates a plant or animal's remains after it dies, sometimes the organism's materials dissolve, and minerals such as calcite, iron and silica replace them. The fossils form in the original shape of the organism, but the composition is different, and it is heavier. This process is known as permineralization.
FLATWOODS EXAMPLES
(A) Terebra unilineata
These gastropods have extremely high spiraled shells with numerous whorls, and the common name refers to the resemblance of their shells to rock drill-type drill bits.. 1.8-5million years old
(B) Cardium dalli
From the Mollusk Family. 1.8-5 million years old
(C) Oculina diffusa (corals)
Miocene coral from the Chipola Formation- about 13 million years old. From the class Anthozoa .Commonly known as the diffuse ivory bush coral or ivory tree coral,
(D) Turritella perattenuata
From the family Turritellidae-extinct . 5-6 inches in length 1.8-2.5 million years old
(E) Spondylus rotundatus
From the family Spondylidae - extinct - about 3 million years old
(F) Scaphella floridana
Gastropods, or snails, have been around since the Late Cambrian period. The class Gastropoda contains a vast total of named species, second only to the insects in overall number. There are 611 known families of gastropods, of which 202 families are extinct and appear only in the fossil record. Coming from Hendry County these are between 1.8 and 12 million years old.
(G) Vermicularia recta
Florida worm snails do not form large clusters, a Florida Pliocene fossil (between 2.5 and 5 million years of age)
(H) Phyllonotus pomum
Known as the apple murex, is a species of large sea snail, a marine gastropod mollusk in the family Muricidae, the murex snails or rock snails.
1.8- 5 million years old
(I) Conus adversarius tryoni
An extinct species of venomus sea snail in the genus Conus It lived from the Early Pliocene until the Early Pleistocene age. It is the only species in the genus that is entirely sinistral (left handed). 1.8-12 million years old
(J) Cypraea problematica
Belongs to the family Cypraeidae.Notable for a strange, very deep slit around the spire. 1.8-5 million years old
References :
1) Revised Edition , "Floridas Fossils : Guide to Location ,Identiication and Enjoyment " by Robin C. Brown
2) Florida Museum of Natural History
3) Wikipedia.
4) Get to know Florida’s fossil pearls – Research News (ufl.edu)
5) How to Identify Shell Fossils | Sciencing
Questions to answer for your smiley :
1) Your task is to identify the most abundant Fossil Shell at Each Waypoint. You will use the ones on this page as reference. No need to write out the scientific name . Just A,B,C and so on.
2) Which of the Shell Fossils do you DO NOT see in quanity at any of the waypoints.
3) From the lesson, how is it possible to once again see where there was once darker colors and patterns on these Shell fossils?
4) Reading the lesson , what does sinistral mean? Which fossil does this refer to?
5) From the lesson last paragraphs we read about Molds,Casts and Permineralization and Petrification. As you went around the route and picked up some of these examples of fossils did you find any of these processes ? If so, which fossil was it happening with?
6) As of June 2019, earthcaches now contain required photo logging tasks. Please provide a photo of yourself, your GPSr, or a personal item with your favorite fossil that you have discovered today.