Answer: We have found fossils that share specific bony traits that are found only in all whales but absent in every other mammal group, indicating descent from a shared common ancestor with modern whales, and these fossils had legs fully adapted for walking on land, and fundamentally identical to those of older mammals that precede the shared common ancestor that these mammals share with whales.
This tells us that the shared common ancestor of whales and these mammals with legs almost certainly had legs themselves, and inherited those legs from their own older mammal ancestors.
Therefore, whales have ancestors in their lineage that walked on land with legs.
(We also have multiple fossils of ancient whales that had legs transitional in form between fully terrestrial walking legs and flippers adapted for swimming, and modern whales still possess a remnant hip bone buried deep in their bodies.)
Hi there!
By both unity and diversity in life, it means that animals and plants (and ecosystems) can be very different from each other but they can also have very similar characteristics. They can work together in harmony but become predator and prey at the same time.
Hope this helps!
Answer:
Matrix of blood
Explanation:
Plasma is known as the upper phase, obtained after centrifugation of the blood. It is essentially the matrix of the blood: water, sugars, salts and small proteins. The rest of the larger components, such as platelets, red and white blood cells will remain in the lower phases, depending on their size and mass.
Autotrophs are organisms that can produce their own food from the substances available in their surroundings using light (photosynthesis) or chemical energy (chemosynthesis). Heterotrophs cannot synthesize their own food and rely on other organisms — both plants and animals — for nutrition.
Explanation: autotroph eg plant
hetrotroph eg animals
They react to external factors like light, temperature etc
