```r
summary_table = starwars %>%
  group_by(species) %>%
  summarise(ave_height = mean(height), var_height = var(height), n_obs = n())

print(summary_table)
```

```
## # A tibble: 38 x 4
##    species   ave_height var_height n_obs
##    <chr>          <dbl>      <dbl> <int>
##  1 Aleena           79         NA      1
##  2 Besalisk        198         NA      1
##  3 Cerean          198         NA      1
##  4 Chagrian        196         NA      1
##  5 Clawdite        168         NA      1
##  6 Droid            NA         NA      5
##  7 Dug             112         NA      1
##  8 Ewok             88         NA      1
##  9 Geonosian       183         NA      1
## 10 Gungan          209.       201.     3
## # ... with 28 more rows
```