Question

name 2 ways that modern horses are different than the ancient ancestors. why did horses evolve at all? why didnt they just stay the same? name 3 ways that modern whales are different from their ancient ancestors. name 3 reasons you can still tell they are related. bellringer for september 12, 2025.

Explanation:

1. Modern horses are different from ancient ancestors due to adaptation to new habitats like grasslands, leading to changes in limb structure for speed and teeth for grazing. Natural selection favored traits beneficial in these environments.
2. Modern whales are different from ancient ancestors because they adapted to an aquatic lifestyle. This led to changes such as the development of flippers, a streamlined body, and blow - holes for breathing. Despite changes, genetic and anatomical remnants show relatedness. We can tell they are related through homologous structures (similar underlying bone structures), vestigial organs (like the remnant of hind - limb bones in whales), and genetic similarities.

Answer:

1. Two ways modern horses are different from ancient ancestors:

• Limb structure: Modern horses have long, slender legs adapted for running on open grasslands, while ancient ancestors had more multi - toed and shorter limbs.
• Tooth structure: Modern horses have high - crowned teeth for grazing on tough grasses, whereas ancient ancestors had different tooth shapes for different diets.
• Reason for evolution: Adaptation to changing environments (expansion of grasslands) and natural selection for traits that enhanced survival and reproduction in those environments.

1. Three ways modern whales are different from ancient ancestors:

• Body shape: Modern whales are streamlined for swimming, while ancient ancestors had a more land - adapted body shape.
• Locomotion: Modern whales have flippers and a tail fluke for swimming, instead of legs like ancient ancestors.
• Respiration: Modern whales have a blow - hole on top of their head for breathing at the water surface, unlike the nasal openings of ancient ancestors.
• Reason we can still tell they are related:
• Homologous structures: There are similar bone structures in the flippers of whales and the limbs of their land - dwelling ancestors.
• Vestigial organs: Whales have remnants of hind - limb bones, indicating their land - dwelling heritage.
• Genetic similarities: DNA analysis shows genetic relatedness to land - mammals.