It is believed that this happens because some signals that regulate development are the same between different species and because <span>they share ancient genes. </span>These ancient genes are expressed during a middle "phylotypic stage" of embryonic development for all species.
For example, human and animal embryos go through very similar stages of early development and share similar features such as tails and gill-like structures. The major difference appears to be how long it takes to reach each of these same stages.
I believe the answer would be D. They create a temporary higher crest
Answer:
The correct answer is Zones of tolerance
Explanation:
All living organisms such as fish,plants and animals need water to survive and also the require certain pH level of water in order to be healthy.Its a acid and base balance reaction.Strong acids dissolve into water and its changes water's pH.if water's pH level drops it becomes acidic suppose a fish waste ammonia releases and dissolves in water to form harmless ammonia ions,carbon dioxide ions and hydrogen ions even some limestone also rises pH level and water becomes more basic.To make the tank water alkaline, add some corals and aerate the tank water by fixing an air pump so that excess of carbon dioxide eliminate out and water pH level comes to neutral this is the reason water becomes slightly alkaline and the fishes are able to reproduce.
Mobile switching station
The mobile switching station is
the most important part of any cellular network. It is associated with communications
functions such as call set-up, release, and routing, locating cellular devices,
assigning frequencies and transmitting signals to the correct sites. It also provides
useful information such as user registration required to support mobile service
subscribers.