February 2016 Biodiversity Spotlight


Photo courtesy of Morgan Schmorgan

Madagascar is an island off the coast of Mozambique, Africa. Total land area is 226,656 square miles (about the size of Texas), making it the fourth largest island in the world. Madagascar is a biodiversity hotspot with a fascinating assemblage of plants and animals, many of which are endemic* to the island, from the long-fingered Aye Aye (Daubentonia madagascariensis), to spikey succulents like the Madagascar Ocotillo (Alluaudia procera featured in the image above). Madagascar has been separated from all other landmasses for approximately 70 million years, and this isolation has led to the high proportion of endemism observed. For example, there are over 11 thousand species of plants that can only be found on Madagascar.

Portal Corner

There are many different ways to explore the biodiversity of Madagascar using the iDigBio portal interface (https://www.idigbio.org/portal/) and different search techniques will give you different sets of results.  Try this example to hone your portal searching skills.

  1. Type “Madagascar” into the Search all fields box at the top of the Search Records page.  This will give you more than 1 million specimen records (the Total is in the middle right of the screen). Look at the map - the records are mostly on the island of Madagascar, but many are not.  Why might that be? (One hint: look at the distrabution of Cassis madagascariensis).
  1. Reset the search, and now enter the text “Madagascar” into the Country filter (field).  How many records do you get now?  Is this a more precise search for island records?
  1. Now try using the Polygon Tools in the top left of the map. Zoom into the island of Madagascar using the + button in the top right of the map and hand tool to move the map around, and draw a rectangle or circle around the island (as best you can).  Is the number of specimen records different?  The polygon tools will only return specimen records for those records which have latitude and longitude data.

Now we encourage you to explore where the Aye Aye and Ocotillo are found on the island!

Want to create links to your searches in the iDigBio Portal? Read the Portal Tutorial to learn how!

*Endemic refers to a species that is only found in a particular geographic area.

By Shelley James and Molly Phillips