Brachiosaurus

# Evolutionary Timeline of Brachiosaurus Brachiosaurus, a massive sauropod dinosaur, evolved during the Mesozoic Era, with its lineage tracing back to early dinosaurs. Key evolutionary pressures included competition for food resources, predation, and changing climates that favored large body sizes and specialized feeding adaptations. Major transitions involved the shift from bipedal ancestors to quadrupedal giants with elongated necks for accessing high vegetation. ### Key Milestones: - **Late Triassic (~230-200 million years ago)**: Emergence of basal sauropodomorphs like Plateosaurus, early ancestors that were bipedal herbivores adapting to diverse plant life. - **Early Jurassic (~200-175 million years ago)**: Transition to true sauropods with quadrupedal stance and larger sizes, driven by abundant fern and conifer forests. - **Middle Jurassic (~175-160 million years ago)**: Diversification of sauropod groups, including precursors to Brachiosauridae, with adaptations for gigantism amid humid, vegetated environments. - **Late Jurassic (~154-150 million years ago)**: Peak of Brachiosaurus, featuring extreme neck length and front limb elongation for treetop browsing, influenced by seasonal droughts and predator pressures.