Final answer:
Key adaptations in the tetrapod skeletal system for terrestrial movement include limbs under the body, decreased adductor muscles, forward limb motion, and rotated limbs for efficient locomotion. The belief that the bulk of native deaths during European exploration were caused by violent conflict is false; disease played a more significant role. The role of Indian alliances in the southeast during European colonization is acknowledged as true.
Step-by-step explanation:
Evolution of the Tetrapod Skeletal System
As animals transitioned from an aquatic to a terrestrial environment, their skeletal systems underwent several adaptive changes to support movement on land. Some of the evolved changes in the animal skeletal system include:
- Limbs placed under the body to decrease the force required for each stride, making land movement more efficient.
- Decreased size of the adductor muscles because limbs were not splayed out to the side anymore.
- Lateral undulating movement of the vertebral column was replaced by limbs swinging forward, reducing the multi-directional movement and concentrating on forward motion.
- Rotation of the femur and humerus, aligning the limbs and digits in the direction of motion.
These changes reduced the energy expenditure for terrestrial locomotion and improved the ability of tetrapods to move and thrive on land.
Impact of European Exploration on Native Populations
The majority of the natives killed during the European exploration period were not slaughtered by Europeans with superior weapons. While conflicts did occur, a significant cause of native population decline was due to diseases brought by Europeans, to which the natives had no immunity.
Indian Alliances in the Southeast
It is true that Indian alliances were an essential means for European empires to establish power in the southeast. These alliances often played pivotal roles in the geopolitical dynamics of the period, affecting both European colonial efforts and Native American societies.
Dimetrodon: A Pelycosaur
Pelycosaurs like Dimetrodon, which possessed sprawling legs and lizard-like movement, represent a stage in the evolution of terrestrial vertebrates. These creatures, despite their primitive aspects, began to exhibit some mammalian traits, such as differentiated teeth, signaling the march towards more advanced terrestrial life forms.