Identifying pollen grains under the microscope may be challenging, especially to the untrained eye. This goes also for a multitude of biological structures with complex shapes, whether embedded in tissues or isolated from their original environment.
The course BIO250 – Palaeoecology at the Department of Biological Sciences in Bergen has now started to use 3D-printed models of pollen grains to help students recognize their many facets and aspects. Providing students with 3D-prints instead of (or in addition to) light- or electron microscopy pictures gives them the opportunity to look at these grains from all possible angles.Let’s take an example with the pollen of Scorzoneroides autumnalis (a.k.a autumn hawkbit). This picture shows the grain (and all its complexity and beauty) under the microscope.
It is however challenging to get an idea of the global shape of the grain based on this single view.
Here is the 3D-print of the pollen grain of the autumn hawkbit. It is approximately 2000 times bigger than the real pollen grain and made of PLA (polylactic acid), a type of bioplastic produced from fermented starch which is both resistant and biodegradable.
The video at the bottom of this article shows the same grain and helps realize how easy it becomes to recognize the features (spikes, cavities, etc) that characterize the species.
For those who have the patience to explore the Internet for hidden treasures, there are millions of 3D models of nearly everything available for download. The National Institute of Health (NIH) provides free models which are relevant for educational activities in the field of biomedical sciences (https://3dprint.nih.gov/). Other commercial platforms also provide models relevant for biology, for free or for sale. Among them are CGTrader, Thingiverse, Free3D, …
Credits and references:
Microscopy picture of Scorzoneroides autumnalis under Creative Commons Attribution-NonCommercial 4.0 International License. Willis, Kathy J (2017). Scorzoneroides autumnalis (169.159.4 – 1). Digitised palynological slide. In: European Reference Collection (Version 4). Obtained from Martin & Harvey (2017) 10.1111/2041-210X.12752. Retrieved from globalpollenproject.org on 10/10/2019.