A particular mountain stream is home to a population of salamanders that are red in color. In the past year, a second population of salamanders that are dark blue in color moved into the same stream. Scientists researching the stream have recently discovered young salamanders that are red with dark blue patches on their bodies.
What can the scientists conclude from this evidence?
The Salamanders are suffering from a bacterial disease
The salamanders are on the verge of becoming extinct
The Salamanders undergo sexual reproduction
The Salamanders undergo sexual reproduction

Although the two theories differ on the evolutionary path of dinosaurs, they agree that

In terms of alternation of generations, the internal parts of the pollen grains of seed-producing plants are most similar to a ) moss sporophyteb) moss gametophyte bearing both male and female gametangiac) fern sporophyted) fern gametophyte bearing only antheridia

Which statements best describe the differences or similarities between a comparative investigation and an experimental investigation? check all that apply. experimental investigations are best for showing cause-and-effect relationships, while comparative investigations do not necessarily show this type of relationship. comparative investigations are often impractical and unrealistic, while experimental investigations are the most practical and realistic kinds of investigations. comparative investigations allow for the use of a wide range of variables but do not have a control group, while experimental investigations involve variables that can be controlled. both experimental investigations and comparative investigations are designed to answer scientific questions. both experimental investigations and comparative investigations focus on making observations rather than collecting new data.