Yes, you can merge them using HTML. When I create tables in .md files from Github, I always like to use HTML code instead of markdown.
Github Flavored Markdown supports basic HTML in .md file. So this would be the answer:
Markdown mixed with HTML:
| Tables        | Are           | Cool  |
| ------------- |:-------------:| -----:|
| col 3 is      | right-aligned | $1600 |
| col 2 is      | centered      |   $12 |
| zebra stripes | are neat      |    $1 |
| <ul><li>item1</li><li>item2</li></ul>| See the list | from the first column|
Or pure HTML:
<table>
  <tbody>
    <tr>
      <th>Tables</th>
      <th align="center">Are</th>
      <th align="right">Cool</th>
    </tr>
    <tr>
      <td>col 3 is</td>
      <td align="center">right-aligned</td>
      <td align="right">$1600</td>
    </tr>
    <tr>
      <td>col 2 is</td>
      <td align="center">centered</td>
      <td align="right">$12</td>
    </tr>
    <tr>
      <td>zebra stripes</td>
      <td align="center">are neat</td>
      <td align="right">$1</td>
    </tr>
    <tr>
      <td>
        <ul>
          <li>item1</li>
          <li>item2</li>
        </ul>
      </td>
      <td align="center">See the list</td>
      <td align="right">from the first column</td>
    </tr>
  </tbody>
</table>
This is how it looks on Github:

 
        
        
` tags did exactly what I was trying to do with the styled list. – Trebor Rude Aug 05 '14 at 16:42
` tags as well.
– Ionică Bizău Aug 05 '14 at 17:04- foo
 
`) also works on Bitbucket Server. – nwinkler Dec 09 '16 at 15:27- Enumeration 1
 - Enumeration 2
 
`. – user3613932 May 04 '20 at 22:30