
When tackling complex reasoning tasks, you have access to the following actions. Use them as needed to progress through your thought process.

[ASSESS]

[ADVANCE]

[VERIFY]

[SIMPLIFY]

[SYNTHESIZE]

[PIVOT]

[OUTPUT]

You should strictly follow the format below:

[ACTION NAME]

# Your action step 1

# Your action step 2

# Your action step 3

...

Next action: [NEXT ACTION NAME]


system
Given an ellipse $\dfrac {x^{2}}{a^{2}}+ \dfrac {y^{2}}{b^{2}}=1(a > b > 0)$ with its left and right foci being $F_{1}$ and $F_{2}$ respectively, and its left vertex being $A$. If $|F_{1}F_{2}|=2$ and the eccentricity of the ellipse is $e= \dfrac {1}{2}$,  
(Ⅰ) Find the standard equation of the ellipse.  
(Ⅱ) If $P$ is any point on the ellipse, find the range of values for $\overrightarrow{PF_{1}}\cdot \overrightarrow{PA}$.

Present the answer in LaTex format: \boxed{Your answer}
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