Final answer:
The boundary between the Paleocene and Eocene epochs was the warmest period in the last 66 million years due to geological and climatic factors, including significant greenhouse gas emissions from volcanic activity and methane hydrate release. This warming contributed to the extinction of certain species and significant climate changes, as understood through the study of paleoclimatology.
Step-by-step explanation:
The boundary between the Paleocene and Eocene epochs is considered the warmest period in the last 66 million years due to several geological and climatic factors that contributed to an exceptional warming event, referred to as the Paleocene-Eocene Thermal Maximum (PETM). During this time, there was a significant release of carbon into the earth's atmosphere, likely from volcanic activity and the destabilization of methane hydrates beneath the ocean floor. The increased greenhouse gases caused a rapid global warming event, which had a lasting impact on the planet's climate and life forms.
The geological changes that occurred during this time contributed to the extinction of certain species, including the existence of cold-adapted megafauna such as the woolly mammoths. This extinction was due to habitat destruction linked to varying temperatures and human activities such as over-hunting.
Paleoclimatology, which is the study of past climates through geological and fossil records, helps scientists understand these significant climatic shifts and trace their effects on biodiversity and the landscape. By examining these records, geologists can piece together the history of Earth's climate and the factors that have influenced its changes, including the extreme warmth of the Paleocene-Eocene boundary.