Biology and History of Woolly Mammoths: PTE Listening: Fill in the Blanks practice questions

Woolly mammoths developed remarkable physical traits that enabled them to survive extreme arctic conditions. Their bodies were covered in a dense outer layer of coarse hair beneath which lay fine underfur that provided critical thermal . In addition to this heavy coat, thick deposits of subcutaneous fat served as energy reserves and shielded internal organs from freezing temperatures. Anatomical also reveal that their small ears and short tails helped prevent heat , which was essential in the harsh tundra. Furthermore, specialised haemoglobin in their blood allowed oxygen to continue efficiently even when ambient temperatures plunged far below levels.

Recent investigations into frozen mammoth remains have yielded fascinating insights into prehistoric herbivorous diets. By studying plant fragments preserved in dental cavities and fossilised dung, researchers can reconstruct the grazing patterns of these massive creatures. It appears that grasses and sedges formed the primary of their daily nutrition, supplemented occasionally by shrubs and mosses during late autumn. Microscopic on their large molars suggest that continuous grinding of abrasive vegetation caused severe tooth over time. This constant wear required a unique system of tooth where new grinding plates gradually emerged from the rear of the jaw to ensure effective food throughout the animal life cycle.

As warming climates altered continental habitats, isolated populations of woolly mammoths survived on remote northern islands for several thousand years. Cut off from the mainland, these restricted herds suffered from a pronounced in genetic diversity. Over generations, persistent inbreeding caused harmful mutations to accumulate across the entire , impairing their immune systems and reproductive . Biochemical studies indicate that these creatures lost olfactory receptors that were crucial for detecting food sources and avoiding toxic plants. This progressive genomic left the dwindling population exceptionally vulnerable to sudden environmental changes and infectious , ultimately accelerating their final extinction.