title: ggplot2 - line up geom_point with split boxplots
body: <p>I am pretty new to R and have been using Google (mainly directing me to this site) to fumble my way into making a passable graph for a project. I am having trouble figuring out what to search for to find other people with the same problem as me so I decided to ask instead.</p>
  
  <p>I have a dataset which looks something like this:</p>
  
  <pre><code>    ATM TEMP PARENT variable value
  1     1    5      1     DEAD     2
  2     1    5      2     DEAD     0
  3     1    5      3     DEAD     1
  4     1   20      1     DEAD     1
  55    1    5      1     LIVE    47
  56    1    5      2     LIVE    42
  57    1    5      3     LIVE    45
  58    1   20      1     LIVE    45
  109   1    5      1 SWIMMING     1
  110   1    5      2 SWIMMING     8
  111   1    5      3 SWIMMING     4
  112   1   20      1 SWIMMING     4
  </code></pre>
  
  <p>ATM represents the pressure experiments were conducted at, TEMP the temperature, PARENT which one of 3 adults the larvae came from and variable represents the condition of the larvae at the given pressure/temperature with the value being how many (It was initially different but I merged them using reshape2).</p>
  
  <p>I have been able to create this graph:</p>
  
  <p><img src="https://i.stack.imgur.com/wUW9W.png" alt="enter image description here"></p>
  
  <p>Using this code:</p>
  
  <pre><code>qplot(factor(ATM), value, data = CONDITION, geom = "boxplot", fill = factor(TEMP)) +
  geom_point(aes(colour=factor(TEMP)) +
  facet_wrap(~ variable, ncol = 1) +
  scale_fill_manual(values = c("lightblue","#FF6666")) +
  scale_colour_manual(values = c("lightblue","#FF6666")) +
  labs(title = "Effect of Pressure on Condition of C.fornicata Larvae") +
  xlab("Pressure \n (atm)") +
  ylab("Number of Larvae") +
  guides(fill=guide_legend(title="Incubation Temp (°C)"),colour=guide_legend(title="Incubation Temp (°C)"))
  </code></pre>
  
  <p>My problem is that the <code>fill=factor(TEMP)</code> is splitting up the boxplots into two (which I want) but the points from the geom_point do not line up with the now offset boxplots. I have tried messing around with the position argument in geom_point but haven't had any luck.</p>
  
  <p>Thanks in advance!</p>