Paleo 200 Notes PDF

Midterm Review Learning Objectives: Lesson 1 1.1 Describe sizes of dinosaurs by comparing modern organisms to dinosaurs Bigger than an elephant, smaller than a chicken. Most are around the same size and mammals we see today including: Rhinos, hippos, elephants and giraffes. 1.2 Identify major bone...

Midterm Review Learning Objectives: Lesson 1 1.1 Describe sizes of dinosaurs by comparing modern organisms to dinosaurs Bigger than an elephant, smaller than a chicken. Most are around the same size and mammals we see today including: Rhinos, hippos, elephants and giraffes. 1.2 Identify major bones and bone types in dinosaur skeletons Vertebrate= backbone Skull Orbits (dinos have two holes behind the orbits), Nares and Fenestrae (holes in front of and behind the orbits) Antorbital (in front of eyes) supratemporal (top behind) lateral temporal (behind) Neck= Cervical Back= Dorsal Hip=Sacral Tail= Caudal Belly ribs= Gastralia Shoulder socket= scapula Hip socket= acetabulum Chevron= tail support bone Humerus- between shoulder and elbow Radius - forearm- thinner Ulna - forearm Carpals - wrist Metacarpals- between wrist and fingers Femur - largest bone in leg Tibia - between knee and ankle Fibula - between knee and ankle - thinner Metatarsals Phalanges ankylankosaursan Forelimbs connect to the pectoral girdle Hindlimbs connect to the Pelvic girdle Largest bone in the body: ilium 1.3 Identify the two major types of pelves in dinosaurs, both by name and general characteristics (i.e. pubis points forwards or backwards) Saurischians- lizard hip- pelvis pointing down Ornithiscians- bird hipped - pelvis pointing back beside the ishium 1.4 Identify the major bony features of general dinosaur groups (i.e. stegosaurs:plates/spikes; ceratopsians:horns/frills; pachycephalosaurs:domes) Theropoda: Sauropods: Hetero Kylosaures: tiny with fangs Ankylosaurus: tail club and osteoderms (armor) Stegosaurus: osteoderm plates on back Hadrosaurus: Iguanodons: thumb spikes Pachycephalosaurus: Dome heads Ceratops: quills on tail 1.5 Discuss the different soft tissues of dinosaurs Muscle Fiber- can see striations on the bones themselves, and scars from where the muscles attached Use birds and crocodiles to see where their muscles attached Trex: jaw muscles are short and broad, and attach to the lower jaw in a way to maximize the power of the bite Giganotosaurus (sauropod): had longer jaw muscles, that meant they did not have as much power but it could close its jaws much faster. In leg bones, there is a crest that the muscles attached to, to help the muscles pull the legs. Soft tissues composed of Keratin- are tough but flexible, like scales and feathers. Melanosomes = pigment cells within a feather In order to be preserved, soft tissues have to be buried right away! Lesson 2 2.1 Classify fossil occurrences 2.2 Recall which environments are best for preserving fossils. 1.​ Wet 2.​ Rivers and Wetlands 3.​ Flat. 4.​ Marine environments 5.​ High sedimentation 6.​ Low 02 2.3 Identify which kinds of rocks preserve dinosaur fossils. Sedimentary Rocks 2.4 Classify types of fossil preservation.  1.​ Permineralization: when the internal spaces of tissue and bones are filled with dissolved minerals carried by water. 2.​ Replacement: occurs when the original material is replaced by minerals. This is no longer the original material. It is a cast, or impression of the original material 2.5 Describe the techniques used to collect, prepare, and curate dinosaur fossils. Process when you uncover a bone: 1.​ Record in notebook 2.​ Grid to map out the location within the quarry To take bone out: 1.​ Cover in wet paper towel acts as a separator 2.​ Plaster and Burlap to protect the bone (protective shell over bones) 3.​ When plaster hardens, flip over and put on other side 4.​ After the plaster is dry, number to indicate which one it is. And where it came from in the quarry. 2.6 Identify taphonomic features common to dinosaur bones. 2.7 Evaluate the taphonomic history of a dinosaur fossil. Lesson 3 3.1 Describe the morphological characteristics of different animal feeding strategies Teeth and Jaws Carnivores: Have sharp teeth to teacher through flesh, sharp claws, serrated edges Frugivores: have rounded curved sharp beaks Herbivores: flat teeth for grinding Birds: sharp recurve beaks and sharp feet, triangular beak for picking up bugs, shore birds have long beaks to probe into sand. Insectivores: They have very sharp teeth for piercing through the exoskeleton of insects, Ant eaters have very powerful limbs and claws for digging up ant hills, termite mounds and rotten logs Piscivores: Eat fish, they do not need powerful jaws, they have long jaws so they can snap fast and pierce fish. Procumnant dentition (allows front tips to impale a fish) Durophagy: Strategy for eating hard shelled things. Powerful jaws to crack bones 3.2 Compare tooth replacement in dinosaurs and humans. Dinosaurs are always growing new teeth 1-2 years replacement (Trex) When the old root becomes resorbed the tooth becomes loose. 3.3 Compare the different ways of processing plant material With dental battery: Hadrosaurus and ceratopsians Gastric mill in birds: This gastric mill is a muscular pouch in the digestive tract near the stomach that holds these swallowed stones, which are called Gastroliths Large gut cavity: In Ankylosaurus and Sauropods (Diplodocus). Giant fermentation tanks, 3.4 Describe various types of non-morphological indicators of diet Cololites: Fossilized gut contents Gastroliths; in aquatic animals Coprolites: fossil poop 3.5 Recall dinosaur diet based on fossil evidence. Lesson 4 4.1 Classify stance in dinosaurs by comparing them to modern animals Erect Stance: Feet directly underneath the animal (ex. Cat) Sprawling Stance: Holds legs out to the side (ex.Lizard) *All modern tetrapods share an ancestor that had a sprawling stance Limbs: Graviportal: Thick and column like (elephant) Carry heavy loads at the expense of speed. Eg. Argentinosaurus Cursorial: smaller, running, longer lower leg bones and walk on their toes or toenails (horse) Opposite. Eg. Ornithomimus 4.2 Evaluate locomotion styles in dinosaurs by comparing with extant animals Cursorial limbs are limbs specially adapted for fast locomotion. Cursorial animals also often stand on their toes (digitigrade posture, Ex. Cheetahs and Ostriches), or stand only on toenails that have been modified into hoofs (unguligrade posture, ex. Horses and antelopes). Humans are not cursorial, and we stand simultaneously on our toes, the flat of our feet, and our heels (plantigrade posture). The ancestor of all dinosaurs was an obligate biped. In Hadrosaurs: Caudofemoralis attaches to the trochanter. Which is the middle of the femur bone. COuldn't take long strides or swing its leg as quickly but it also wouldn't tire out quickly. In tyrannosaurus: The caudofemoralis is attached higher up, closer to the hip. This means that it could swing its leg fast and could probably take longer steps. (muscle doesnt have to expand as far) but they would tire out more quickly. Tyrannosaur would win in a sprint but a hadrosaur would win in a marathon. 4.3 Interpret ichnofossils for what type of locomotion is represented Ichnofossil: any track or trail left behind my an animal -​ The distance between marks can tell us how fast an animal was moving -​ Size of an animal from the size of its footprint. 4.4 Evaluate the evidence for warm- or cold-bloodedness in Dinosaurs. Osteons are laid down in distinctive ways between endotherms and ectotherms. Cube-Square law: If you have a relatively large body volume and a relatively small surface area, your internal temperature is much less affected by your external environment Gigantothermy: Animal that is so large its internal temperature is unaffected by external environment. - Meaning that if they were not exactly endothermic, they would have been able to take advantage of many of the endothermic benefits. Like speed and continuous activity Lesson 5 5.1 Describe the characteristics of a dinosaur egg. Dinosaur inherited this hard shelled egg laying ability. Even so, hard shells had to remain relatively thin in order to facilitate oxygen exchange with the air. So even hard shelled eggs remained susceptible to predators. 5.2 Define terms related to the gross anatomy and histology of bones. Histology is the technique of slicing samples of bones into very thin sections, such that the internal structure of the bone can be observed under magnification. Bone cells are called osteons. During seasonal periods, when resources needed for growth are scares, such as during winter or the dry season, growth may slow down. This creates rings inside the bones, analogous to those of a tree trunk. These rings are called lines of arrested growth, or LAGs for short. remodeling, where the old bone cells were replaced by newer bone cells This kind of bone is called Haversian, or secondary bone, external fundamental system (EFS). The presence of an EFS indicates that the dinosaur is skeletally mature and has stopped growing. 5.3 Evaluate the evidence for identifying individual dinosaurs as juveniles or adults. Younger dinosaurs: -​ Less prominent facial extrusions -​ Larger eyes -​ Smaller size -​ Shorter relative limbs -​ Larger Head Bones of juveniles: -​ High vascularity -​ Lamellar bone Ontogenetic changes: Changes in the phenotype of an individual during its life span Isometrically: Grew in absolute terms but maintained the same proportions 5.4 Evaluate the evidence for determining whether or not a dinosaur was male or female. Bone histology: Female dinosaurs would have had to put a lot of energy into laying eggs. They would also need a surplus of calcium to form the eggs. This calcium is taken from the dinosaurs bones. Trade off: more calcium to make strong shell would mean weaker bones -​ Medullary bone: Months leading up to the birth, they would store calcium in the marrow cavities of the bones, then when it was time to steal the calcium, they would take from the storage rather than the supporting bones. Marrow cavities: space in bones these calcium stores are only found in egg laying females. 5.5 Evaluate the evidence for or against parental care in different groups of dinosaurs. High: theropods and hadrosaurs Low: Sauropods Sauropods were large so they could lay lots of eggs- like sea turtles Large theropods had large growth rates: were grown fully in 20 years. Lesson 6 6.1 Identify potential defensive and predatory adaptations in dinosaur skeletons Defensive: Fighting weapons (horns, spikes) Herding Keen eyesight and hearing Armor Speed Predatory: 6.2 Suggest predatory behaviours and styles in carnivorous dinosaurs Fighting, ambushing, stealthy, pursuit, cooperation, social 6.3 Suggest potential intraspecific behaviours in dinosaurs Battles within a species: Pachycephalosaurus: attacking head to head Tyrannosaurs: Fighting between males defending territory or sparring for mates. 6.4 Identify other fossil evidence for defensive, predatory, or other intraspecific behaviours in dinosaurs Marks on bones