Exam 4 Flashcards
Theory
a universal explanation for a wide range of phenomena
Hypothesis
A tentative explanation for natural phenomena (an educated guess)
Fact
An agreed-upon interpretation of observations.
Law
A statement describing the relationship between two or more phenomena
Model
A representation of a real-world phenomenon that emphasizes some aspect of that phenomenon.
Proof
the results of an investigation either support, or do not support the hypothesis being tested. In science there is always room for alternative explanations, as long as they are consistent with the data.
Falsifiability
that is there has to exist some set of circumstances that if they occurred they would show that the idea is false.
Paradigm shift
a fundamental change in the basic concepts and practices of a particular field or discipline. It involves a new way of thinking that alters how people understand and approach problems.
Grade
levels of evolutionary development. Ex: reptile grade includes cold-blooded physiology and scales. Mammal includes warm-blood physiology, mammary glands, and hair.
Clade
evolutionary lineages, or a group of species that includes an ancestral species and all of its descendants. Ex. Organism in different grades can be included in the same clade if they are descended from a common ancestor.
Anapsid
refers to a type of skull that has no openings (or “fenestrae”) behind the eyes.
no temporal opening
Diapsid
two openings behind the eyes, that are for the jaw muscle to get larger. Clade Eureptilia, clade Archosauria and Lepidosauria
Synapsid
refers to a type of skull that has one opening behind the eyes.
Tetrapoda
4 limbed vertebrates
Amniota
clade of vertebrates that includes reptiles, birds, and mammals. They are characterized by having an amniotic egg.
Synapsida
major clade of amniotes characterized by having a single temporal fenestra in the skull
Sauropsida
reptiles and birds, under this group there is the parareptilia and eureptilia.
Eureptilia
clade within the group of reptiles that includes most modern reptiles, such as lizards, snakes, and crocodiles, as well as their extinct relatives. (two temporal fenestrae (openings) in their skulls)
Lepidosauromorpha
scaled lizard forms (snake lizards…)
Archosauromorpha
rulling lizard form, broader grouping of reptiles that includes most modern reptiles and their ancestors. Specifically, Archosauromorpha comprises the archosaurs—birds and crocodilians—and their close relatives.
Crurotarsi
crocodiles, alligators and gavials.
Ornithodira
is a clade within Archosauromorpha that includes pterosaurs (flying reptiles) and the dinosaurs (including birds). It is characterized by specific skeletal features, such as an elongated metatarsal and an upright stance.
Dinosauria
terrible lizards, clade that includes all dinosaurs, a diverse group of reptiles that dominated terrestrial ecosystems
Saurichia
This includes theropods (like Tyrannosaurus and modern birds) and sauropodomorphs (like Brachiosaurus).
Ornithischia
group includes various herbivorous dinosaurs such as Stegosaurus and Triceratops.
Theropoda
beast-footed dinosaur
Sauropodomorpha
lizard footed dinosaur
Ornithopoda
duck, billed dinosaur
Thyreophora
armored dinosaur
Marginocephalia
fringe-Headed dinosaur
Erect stance
an upright posture with the body standing vertically, typical in humans and some animals.
Sprawled stance
a posture where the limbs extend out to the sides, common in many reptiles.
Semi-erect stance
a middle posture where the body is partly upright, with limbs positioned somewhat to the side and back.
Microevolution
evolution within a species (adaptation)
Macroevolution
the creation of new species and higher taxonomic categories.
Natural selection
A mechanism for evolution.
Differential survival and reproduction of phenotypic (what it looks like) and genotypic (genes that create that phenotype) variant.
Sexual selection
selection in which members of one gender select mates from the opposite gender based on some measures of quality.
Genetic drift
a change in allele frequency by chance alone
Founder effect
a change in allele frequency (generally a loss of genetic variation) in a new population as the result of creating the population from a subset of a larger population.
Population bottlenecks
a severe reduction in the number of individuals in a population with subsequent recovery of the population’s size.
Heterochrony
a change in the pattern of allometric growth, a change in the timing of life-history events.
Paedomorphosis
evolutionary process in which an organism retains juvenile features into adulthood.
Peramorphosis
evolutionary process in which an organism develops exaggerated adult features or characteristics beyond those of its ancestors.
Hox genes
(master gene), control other genes, operate by controlling the functioning of structural genes
Structural genes are responsible for making the structure of the body.
Stratigraphy
the study of the order and relative position of strata
Superposition Principle
it believes that the youngest layers of the earth at the top and the oldest layers at the bottom.
Relatie dating
layers at the lower strata are older and layers at the higher strata younger but not sure how old or young
Numerial dating
Based on radioactive decay you can determine how old a layer is.
Endothermic
obtaining heat from an internal (endogenous) source
Ectothermic
obtaining heat from the environment
Poikilothermic
a variable body temperature
Homeothermic
a constant body temperature
Inertial homeothermy (gigantothermy)
Ability of certain animals to maintain a stable body temperature due to their body temperature mass and low heat loss
Oviparous
egg-laying
Viviparous
live birth
Ovoviviparous
live birth without direct maternal contribution to the embryo
Parthenogenesis
development of an egg without the help of a male
Precocial young
young are able to move aroudn easily shortly after birth
Altricial young
young are nest-bound, wholly dependent on parent for food.
Alpha Decay
Atomic mass lose 4
Atomic number lose 2
Beta Decay
don’t change atomic mass increase 1 atomic number
Gamma Decay
Dangerous rays
doesn’t change atomic number, doesn’t change atomic mass, gamma rays the worst.
Radioactive half-life
The interval of time required for one-half of the atomic nuclei of a radioactive sample to decay.
Local extinction
The loss of an organism in a local area.
Global extinction
The loss of an organism from the planet.
Background extinction
The constant, low level loss of species from the planet.
Mass extinction
The loss of a significant portion of the organisms that had been alive during a fairly short time period.
Cyclic Mass Extinction
Mass extinctions that occur on a repeating regular basis.
Siberian Traps
similarity: both result of extensive volcanism, indicative of volcanic activity going on for a long time, associated Permian extinction, older
Area of an extensive lava.
Lava that covers 2 km thick almost a 1 million square miles that covers.
Deccan Traps
associated with the dinosaur extinction, extensive volcanism
Extensive volcanism, Located in India or where India was, 65 million years ago.
2,000 meters thick.
Covering 500,000 km2 (193,051square miles)
Antarctic Crater
Evidence of a bolide Crater in Antartica dates about 250 million years ago.
Chicxulub
massive crater buried under Mexico’s Yucatán Peninsula. It was created about 66 million years ago when a huge asteroid or comet hit Earth. This impact is believed to have caused the mass extinction of the dinosaurs by triggering massive fires, a “nuclear winter” from dust blocking sunlight, and drastic changes to the climate.
Shiva Bolide Crater
Crater right next to India, dates about 65 million years ago,
Describe the importance of falsifiability, uniformitarianism, proof, and truth without certainty to the process of science.
Falsifiability
Importance to Science: Falsifiability allows science to self-correct by discarding or revising hypotheses that do not align with observed data. It separates science from pseudoscience, ensuring that only testable and refutable ideas are pursued.
Uniformitarianism
Importance to Science: This principle underpins fields like geology and evolutionary biology, enabling scientists to infer historical phenomena using current evidence. It promotes consistency and predictability in scientific models of Earth’s processes.
Proof
Importance to Science: Scientific proof provides confidence in a hypothesis while maintaining flexibility for new evidence. It allows science to advance through incremental and evidence-based understanding, rather than claiming immutable truths.
Truth Without Certainty
Importance to Science: This concept drives continuous inquiry and avoids dogmatism, recognizing that science evolves as new tools, data, and methods emerge. It fosters humility and adaptability in the scientific process.
Identify the major clades to which the dinosaurs belong and where these clades diverge from amphibians, mammals, snakes and lizards, and crocodilians.
- All are Tetrapoda
- All except Amphibians are amniotes
- Snakes + Lizards are Lepidosauria
- Mammals are Synapside
- Crocodilians are Crurotarsi
- Mammal, crocodilians, dinosaurs are archosauria
- Dinosaurs are ornithodira
o Birds are therapod
Describe how natural selection, sexual selection, genetic drift, the founder effect and
population bottlenecks affect evolution by changing the genetic make-up of a population.
Describe the rock cycle and how one form of rock can be transformed into another.
The rock cycle is a continuous process in which rocks are transformed between three main types: igneous, sedimentary, and metamorphic, through processes like melting, cooling, weathering, erosion, compaction, and heat or pressure.
Describe the mechanism of plate tectonics and how it relates to continental movement, volcanoes, earthquakes, and mountain building.
Plate tectonics is the theory that Earth’s lithosphere is divided into rigid plates that float on the semi-fluid asthenosphere, driven by convection currents in the mantle. This movement causes continental drift, volcanic activity at plate boundaries, earthquakes from plate interactions, and mountain building through collisions or uplift.
Describe the evidence for and possible roles that plate tectonics, extensive volcanism, and bolide impacts had in the end Permian and end Cretaceous extinctions.
Evidence for the end-Permian extinction includes massive volcanic activity in the Siberian Traps, which released greenhouse gases and toxins, causing climate change and ocean anoxia, while potential tectonic-driven shifts disrupted ecosystems. For the end-Cretaceous extinction, the Chicxulub bolide impact caused widespread fires, tsunamis, and a “nuclear winter,” amplified by Deccan Traps volcanism, which further destabilized Earth’s climate and biota.
Articulate both pro and con arguments in relation to several lines of evidence related to dinosaurs being endothermic.
Pro: Evidence like the high metabolic rates inferred from growth rings in dinosaur bones, bird-like respiratory structures, and predator-prey ratios suggest dinosaurs were endothermic, enabling sustained activity.
Con: Counterarguments highlight the lack of direct evidence for warm-blooded physiology, with some pointing to large size and gigantothermy as alternatives for temperature regulation, as well as traits shared with ectothermic reptiles.
Describe the roles of the collar bone and feathers in determining the dinosaur-bird evolutionary connection.
The collarbone (or furcula) is a key feature linking dinosaurs to birds, as it provides structural support for flight muscles and is found in theropod dinosaurs closely related to birds. Feathers, originally serving insulation or display functions in non-avian dinosaurs, highlight a gradual evolutionary transition, culminating in their role in flight for early birds like Archaeopteryx.
