the answer is: The neutral stimulus causes no response.
Without being paired by any situation, neutral stimulus would not mean anything to the subjects. Because of this , the subjects would normally just ignore the neutral stimulus every time they face it.
But, when the neutral stimulus is paired with a certain situation (such as ringing a bell before giving foods to dogs), the dogs will associate the neutral stimulus with the positive reinforcement. To the point where the neutral stimulus transformed into a conditioned stimulus, which make the dogs'mouth to start watering every time they hear the bell.
This answer is true Geographic isolation is the main cause of speciation.
Hybrid organisms always produce sterile offspring.
If a population is spread out over too large area, they may become extinct.
Buddhist religion<span>. they were buddhist monks </span>
<span>The Union victory in the Civil War in 1865 may have given some 4 million slaves their freedom, but the process of rebuilding the South during the Reconstruction period (1865-1877) introduced a new set of significant challenges. Under the administration of President Andrew Johnson in 1865 and 1866, new southern state legislatures passed restrictive “black codes” to control the labor and behavior of former slaves and other African Americans. Outrage in the North over these codes eroded support for the approach known as Presidential Reconstruction and led to the triumph of the more radical wing of the Republican Party. During Radical Reconstruction, which began in 1867, newly enfranchised blacks gained a voice in government for the first time in American history, winning election to southern state legislatures and even to the U.S. Congress. In less than a decade, however, reactionary forces–including the Ku Klux Klan–would reverse the changes wrought by Radical Reconstruction in a violent backlash that restored white supremacy in the South. hope this helps if your want to read it all lol
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