How many gifts were given in the 12 days of christmas .

Ben is interested in using a source that provides original research, current and developing trends and experts within specific fields. which source should he use?

Snakes, dogs, and humans have a vertebral column. snakes and dogs have tails, and humans have vestigial tailbones. dogs and humans have limbs, but snakes do not. most reptiles lay eggs, but a few give birth to live young. what do these structures suggest about the evolutionary pattern between the three organisms? 1. snakes and dogs are more closely related than snakes and humans. 2. snakes and humans are more closely related than humans and dogs. 3. dogs and humans are more closely related than snakes and humans. 4. dogs, snakes, and humans share a common ancestor. 5. the early ancestor of snakes and dogs is the same, and the early ancestor of humans is different.

The graph shows the populations of two species over time. which type of symbiotic relationship does the graph represent? a. commensal b. mutualistic c. parasitic d. parent-offspring e. predator-prey