AMNH Excursion:
Nov 16:
The field trip to the AMNH offered an incredible opportunity to engage with various facets of science and natural history. I participated in three fascinating tours guided by experts from Merck and Fletcher, a self-guided exploration, and viewed the Space Show: Worlds Beyond Earth. The Merck tour focused on the evolution of vertebrates and the transition from water to land. The oldest known vertebrates were jawless fish, like hagfish, which lack the cartilage-based internal skeletons of their descendants. The appearance of jawed vertebrates marked a significant evolutionary leap, leading to the rise of cartilaginous fish like sharks. Despite common misconceptions, sharks are not the oldest creatures on Earth but have ancient ancestors that developed traits like cartilage skeletons and sharp, self-sharpening plates. The tour also highlighted the evolution of bony vertebrates, particularly ray-finned and lobe-finned fish. Fossils revealed fascinating insights, such as a fish that swallowed another fish before being fossilized, providing a snapshot of ancient behavior. The lobe-finned fish, once thought extinct, were rediscovered by an amateur scientist in South Africa. These fish have fins analogous to human hands, representing an evolutionary precursor to terrestrial limbs. A model of Acanthostega illustrated one of the first tetrapods capable of living on land and water. It possessed open gill slits for breathing and a unique limb structure, with eight fingers and seven toes. These adaptations, along with a hip capable of supporting occasional land movements, were likely driven by single-point mutations. Over millions of years, fossils showed the gradual adaptation of vertebrates to fully terrestrial life, including healed leg bones indicating comfortable land locomotion. The tour concluded with the diversification of vertebrates into reptiles, mammals, and herbivores. Key highlights included the evolution of turtles, whose unique shells are fused vertebrae and ribs, and the discovery that turtles share a common ancestor with archosaurs, a group that includes crocodiles, dinosaurs, and birds.
The Fletcher tour delved into animal morphology and environmental interactions. We learned about the differences between antlers and horns, both of which serve purposes in fighting and attracting mates. An intriguing example was the pronghorn, North America's fastest land animal, which evolved its speed to escape ancient predators like cheetahs. The tour also covered the effects of DDT on bird populations, illustrating how pesticides disrupted prey and predator cycles. Birds exposed to DDT laid fragile eggs that often broke, causing a sharp decline in bird numbers. This discussion underscored the delicate balance of ecosystems and the far-reaching consequences of human activity. Corals were another focal point, showcasing their symbiotic relationship with algae. During the day, corals perform photosynthesis, while at night, they use stingers to capture food. The tour also highlighted variations within species, such as the box turtle, and the methods used to study these differences, including bone staining and specimen preservation techniques. One fascinating section covered fossilized traces left by animals, such as footprints and burrows, which provide insights into behavior and interactions. The tour concluded with a discussion on the preservation of insects, wet specimens, and field notebooks, emphasizing how every detail matters when studying natural history. During the self-guided tour of the Hall of North American Animals, I had the opportunity to explore a variety of species native to the continent. The exhibit highlighted the diverse ecosystems of North America, showcasing animals such as bison, bears, foxes, owls, and many others. Each display provided insight into the unique adaptations these creatures have developed to survive in their environments, from the harsh conditions of the tundra to the lush forests and grasslands. The exhibit also emphasized the evolutionary pressures that shaped their physical characteristics and behaviors, giving me a deeper understanding of how species have evolved over time. Additionally, the Hall of North American Animals underscored the importance of conservation efforts in preserving these habitats and ensuring the survival of these incredible creatures for future generations. The Space Show: Worlds Beyond Earth, narrated by Lupita Nyong’o, provided a breathtaking journey through the solar system. Starting with the Moon, we explored its volcanic past and the role of lunar rock samples in understanding the Moon’s formation from a collision with Earth. The show highlighted Jupiter’s moon Io, the most volcanically active object in the solar system, and Europa, with its subsurface ocean potentially harboring life. Saturn’s moon Titan stood out with its methane lakes and Earth-like weather systems, revealing the diversity of environments in the outer solar system. Closer to home, Venus and Mars served as cautionary tales of planetary change. Venus’s runaway greenhouse effect contrasts starkly with Mars’s dry, frozen landscape, demonstrating the fragility of habitable conditions. The program concluded with Earth, emphasizing its magnetic field, dynamic geology, and life-sustaining atmosphere, portraying our planet as a "grand oasis in the vastness of space." This field trip was an exploration of evolution, environmental science, and planetary systems. Merck tour’s insights into vertebrate evolution, Fletcher’s exploration of ecosystems and the immersive Space Show, deepened my appreciation of the natural world and my place within it.