Prehistoric Visitors To Pamperin Park
In Wisconsin, United States
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A fossil is basically…A ROCK. A rock which basically can "ONLY" be found within sedimentary type rock layers. The use of the word fossil refers to the physical evidence of a life form that existed before recorded human history. This prehistoric evidence includes the fossilized remains of once-living organisms, impressions and/or molds of their actual physical form and marks/traces created in the sediment by their activities, such as tracks and burrows. The scientific community has dated the oldest analyzed single cellular fossil discoveries to be approximately 3.5 billion years old. As for the purposes of fossil hunting and collecting by the general populous, fossils of this size are not collectible. It wasn't until approximately 600 million years ago that complex multi-cellular life began, and it was then that an actual collectible fossilized record began. Only a very small proportion of plant and animal life that has ever existed will ever make it into this fossil record. After death most living organisms simply decay and are recycled back into the earth, leaving no trace of their existence.
Conditions needed for fossilization include (but are not limited to) a rapid burial (which protects the specimen from environmental or biological disturbances), oxygen deprivation (which limits the extent of decay), a continued sediment accumulation (as opposed to an eroding landscape) and a long-term burial with the absence of excessive heating and/or compression (which could possibly destroy the original shape or form of the organism being fossilized). Fossils are typically formed within sediments that have been deposited beneath water levels, as the conditions needed for fossilization, occur more frequently in this type of environment. Even fossils derived from land (i.e. dinosaur bones and other land organisms) were ultimately preserved in sediments deposited beneath water such as wetlands, lakes and rivers.
Trilobites were some of the first multicellular creatures to live in the world's oceans. The fossil record of these creatures extends back nearly 600 million years ago, to the early part of the Cambrian Period. Long before fish inhabited the oceans and Dinosaurs roamed the land, Trilobites made their appearance. Trilobites flourished as swimmers, crawlers and burrowers for 350 million years. They were hard-shelled creatures with jointed legs. The name Trilobite means three lobed one. This refers to their bodies, which were divided into three parts: the head (cephalon), thorax (chest) and the tail (pygidium). They are the earliest known animals to possess vision. Their fossils take on the appearance of segmented mollusks (chitons) or aquatic insects (water pennies). Personally, they always reminded me of Atlantic horseshoe crabs. See photo above of a Trilobite fossil.
Crinoids are marine animals of the same family as starfish, sea cucumbers, sea urchins, brittle stars and sand dollars. The name Crinoid comes from the Greek words krinon and eidos, meaning lily form. They resemble underwater flowers that can still be found in ocean waters to this day and are often called sea lilies. They are characterized by a food filtering mouth at the top surrounded by feeding arms. A stem then connects this bud to what has the appearance of a rootball. This rootball is used in attaching themselves to the ocean bottom. Many limestone beds, dating back to the late-Paleozoic era (500MYA), consist almost entirely of crinoid skeletal fragments. Crinoid fossils have the appearance of tiny rings (sections) or stacks of rings (stems). See above photo.
The name brachiopod comes from the Latin words for arm (brachio) and foot (pod). Brachiopods first appear as fossils dating back to the earliest days of the Cambrian period, around 500 million years ago. Although relatively rare, they still exist in today's oceans and seas. Because of this fact, they are considered to be living fossils. Though they appear to be similar to clams and oysters they are not even mollusks, but are more closely related to bryozoans. Most are permanently attached by a fleshy stalk (pedicle) to a hard, sea-floor surface, rock outcrop or boulder and are incapable of actively pursuing food. They survive by filter feeding upon microscopic organisms and bits of organic matter. They were possibly the most abundant animals of the Paleozoic era and important contributers to the building of ancient reefs. They may also be the most plentiful fossils found on earth. See above photo.
Orthoceras, also known as straight horn, is a genus of extinct nautiloid cephalopod (mollusk) that lived from the Ordovician Period to the Triassic Period (500 - 200 million years ago). They are related to the present day Squid, Octopus, Cuttlefish and Nautilus. They had long, straight shells with their soft body tissue contained within the last open-ended chamber at the large end of the conical shell. As they grew in size and the housing segment became too small, a dividing wall (septa) grew and a new chamber was formed, creating a new, larger housing compartment. A tube running lengthwise, called a siphuncle, was used to pump air and liquid into the septa, helping to achieve neutral buoyancy and to propel them through the waters. They had 8-10 tentacles like their modern-day relatives with an advanced nervous system, jaws and eyes. They fed mainly on floating plankton, small trilobites and other gastropods found near the ocean floor. See above photo.
Bryozoans, also known as sea mats, moss animals or lace corals, are microscopic sea animals that live in colonial type environments and superficially resemble corals. Because these colonial structures are usually composed of secreted calcite, they commonly form fossils. Bryozoan fossils occur in many shapes and forms, including finger-shaped, fan-shaped, spiraling fans, mats and massive irregular mounds. Many of the fossils will show pits where the individual bryozoans attached themselves and spent their entire lives, unable to move. They fed on microscopic organisms within the water flow, which they captured with tiny tentacles. There are around 5000 currently living species with several times that number having been discovered within the fossil record. See above photo.
Trace fossils (or ichnofossils) are the remains of burrows, trackways, nests, droppings (coprolites), eggs and other types of impressions. Fossilized trackways and burrows, showing how creatures lived underground, are just as important as tracks, nests and coprolites which show life above ground. In general, trace fossils help scientists to get a larger picture of how an animal lived and not just how it looked.
Micro and Macro Fossils
A microfossil is a fossilized plant or animal whose size is at, or below, the level at which it can be seen by the naked eye. The commonly applied cutoff point between micro and macro fossils is approximately 1 mm. Microfossils may either be complete, or near-complete, organisms in themselves such as the marine algae or plankton. They can also be individual parts of an organism, such as teeth or spores.
Fossil resin (generally called amber) is an excretion produced by certain plants for their own protection from insects or to seal wounds. This type of fossil often contains other fossils trapped within, which can include bacteria, fungi, plants or animals. Animal inclusions are usually small invertebrates, predominantly arthropods, such as insects and spiders. Small fragments of DNA can sometimes be found within these types of fossils. This process is also called unaltered preservation since the original specimen remains.
A living fossil is a term used for any living species that closely resembles, or is apparently identical to, a species previously known only from fossil discoveries. Included in this list are the lobe-finned coelacanth (fish), monoplacophoran mollusk (invertabrate) and the Chinese maidenhair tree. A living fossil can also be a single living species with no close relatives such as the New Caledonian Kagu (bird) or the Sunbittern (bird). It can also be a small group of closely-related species with no other close relatives, such as the oxygen-producing, primordial stromatolite, inarticulate lampshell lingula (brachiopod), many-chambered pearly Nautilus (cephalopod), rootless whisk fern, armored horseshoe crab and dinosaur-like tuatara (reptile). These are the sole survivors of once large and widespread family groups now found only in the fossil record.
Pseudofossils (fake fossils) can easily be mistaken for real fossils. A dendrite, a type of pseudofossil, is actually a visual pattern formed when circulating groundwater flows between rock layers, leaving behind manganese dioxide crystals in distinct flat, branching patterns. This type of fossil is produced by naturally occurring geologic processes and not by biologic processes. Other types of pseudofossils include kidney ore (round shapes found in iron ore) and moss agates (which look like moss or plant leaves). Concretions (once thought to be dinosaur eggs) are round or ovoid-shaped nodules found in many types of sedimentary rock and are often mistaken for fossils as well. This type of fossil generally has a symetrical shape/pattern to its formation.
ATTN: Park Hours 8AM until Sunset Only!!!
The coordinates given are for parking only. Proceed to the nearby bridge, passing through the nearest archway. Stop when you are standing under the archway on the other side of the creek. Both of these archways are constructed of various rocks garnered from the surrounding landscapes of Northeastern Wisconsin. Once directly under the second archway (coordinates listed below), look to your right about 5 feet up. Use the "large center rock" to answer the questions listed below. The rock in question is covered in one, and only one, type of fossil listed above. Send your answers to me using the link found on the cache page. You do not have to wait for conformation from me to log your find. Pictures are welcomed and appreciated as long as they do not show the rock in question. The answer to #1 is in the readings above. The answers to #2 and #3 will need researching on your own.
1. What type of fossil is found covering the rock in question? (Brachiopod, Bryzoans, Resin, Orthoceras, Crinoid, Trilobite, Living, Trace, Micro/Macro or Pseudofossil).
2. Is the rock in question Sandstone, Rhyolite, Limestone or Granite? (possible internet search required).
3. Is the rock in question Igneous, Sedimentary or Metamorphic in nature?
(No hints available.)
Last Updated: on 8/24/2017 6:01:53 AM Pacific Daylight Time (1:01 PM GMT)
Coordinates are in the WGS84 datum