Dinosaur Extinction
BIOL2110- Vertebrate Zoology
Word count: 1056
Dinosaur extinction: An analysis of events and theories that possibly led to the dinosaurs' demise.
Ever since the history of Earth has been studied using fossil records, extinctions have always been the object of fascination and interest, particularly the mass extinctions that occurred throughout Earth's history. A mass extinction can be caused by disruptive global environmental changes, where large numbers of species have become extinct (Urry et al. 2008). There have been five major extinctions documented based on fossil records over the past 500 million years, but the Cretaceous (KT boundary extinction – a name that meant it began the Tertiary era) extinction caught a lot of attention (Elewa et al 2009). This event extinguished more than half of all marine species and eliminated many families of land (terrestrial) plants and animals, including most of the dinosaurs. Finding out how this extinction occurred included theories about a combination of natural disasters, the already decreasing population of the dinosaurs and an asteroid impact that either magnified the already reduced population of dinosaurs to extinction, or single-handedly did the damage. An evaluation of theories and hypotheses is essential in order to really understand what caused the dinosaurs' demise, through analyzing evidence presented. The survival rates of all the organisms during the KT boundary (Cretaceous period),are a strong indication that no single cause is sufficient to explain the extinction that occurred (Brusatte et al. 2010). Together, however, almost everything that could go wrong did so surrounding the K/T boundary: shrinkage of habitats, climate change, Deccan volcanism, and the asteroid impact all occurred. The combination of these biotic stresses led not only to the dinosaurs' extinction, but the extinction of a variety of plants, marine reptiles, diatoms, dinoflagellates, and nannoplankton (Elewa et al. 2009).
Word count: 1056
Dinosaur extinction: An analysis of events and theories that possibly led to the dinosaurs' demise.
Ever since the history of Earth has been studied using fossil records, extinctions have always been the object of fascination and interest, particularly the mass extinctions that occurred throughout Earth's history. A mass extinction can be caused by disruptive global environmental changes, where large numbers of species have become extinct (Urry et al. 2008). There have been five major extinctions documented based on fossil records over the past 500 million years, but the Cretaceous (KT boundary extinction – a name that meant it began the Tertiary era) extinction caught a lot of attention (Elewa et al 2009). This event extinguished more than half of all marine species and eliminated many families of land (terrestrial) plants and animals, including most of the dinosaurs. Finding out how this extinction occurred included theories about a combination of natural disasters, the already decreasing population of the dinosaurs and an asteroid impact that either magnified the already reduced population of dinosaurs to extinction, or single-handedly did the damage. An evaluation of theories and hypotheses is essential in order to really understand what caused the dinosaurs' demise, through analyzing evidence presented. The survival rates of all the organisms during the KT boundary (Cretaceous period),are a strong indication that no single cause is sufficient to explain the extinction that occurred (Brusatte et al. 2010). Together, however, almost everything that could go wrong did so surrounding the K/T boundary: shrinkage of habitats, climate change, Deccan volcanism, and the asteroid impact all occurred. The combination of these biotic stresses led not only to the dinosaurs' extinction, but the extinction of a variety of plants, marine reptiles, diatoms, dinoflagellates, and nannoplankton (Elewa et al. 2009).