Picky finches: It’s all in the beak!


Welcome to evolution in action! Learn about the adaptive radiation of Darwin finches into the 18 species present on the Galapagos Islands today.

Darwin finches are iconic due to the great variation in their beak shapes and sizes, the result of specialisation toward food sources. Here we match the bird to its niche – by matching the best tool to the type of food.


Swedish summary:

Välkommen till ”evolution in action”! Lär dig om den adaptiva radieringen av Darwinfinkar i de 18 arter som finns på Galapagosöarna idag.

Välkommen till ”evolution in action”! Lär dig hur de 18 arterna av Darwinfinkar som finns på Galapagosöarna har utvecklats genom adaptiv radiering.

Darwinfinkar är ikoniska på grund av den stora variationen i deras näbbform och storlek. Detta är resultatet av specialisering mot olika typer av födor. Här matchar vi fågeln till sin nisch genom att matcha vilket verktyg som passar bäst till vilken typ mat.



About 1.5 million years ago, a small group of birds from South America flew to Galapagos and started their remarkable journey of speciation. They rapidly colonized different islands, and adapted to the local environments. One of the iconic features is their diversified beaks, depending on food resources found on the respective island. Till today, they have evolved into 18 identified species. They are well known as Darwin’s finches.


The activity

The children will be given the opportunity to solve a puzzle related to beak size/shape and foraging ability! There are three types of food and three types of pliers and they will have to choose the best pliers for each type of food.

On the table will be three boxes and attached to the table with string /chains will be two sets of three pliers – one set on each long side of the table. The activity is to match the appropriate plier to the foraging task. On the string/chain to each plier will be a laminated, printed circle showing the finch head, particularly the beak which the pliers represent.

  1. A block (with a cactus motif) with holes drilled into it. In the holes, we will place small seeds – like sesame seeds. Only the long slender pliers will fit these holes and allow access to this forage.
  2. A box (with ground motif) holding a couple of large chestnuts (or other appropriate nut/seed). The large, wide mouthed pliers will be the only one that can pick up these “large, hard to crack seeds”
  3. A box (with tree motif) holding gummy worms. The regular grabby pliers will suffice to pick up these “insects”

A bonus activity: Poster board with map
Match finch beak to habitat and populate the islands!




Resources of interest