platinum group elements migrated to where the iron was

An example of teleology* in popular science writing:

"The PGEs [platinum group elements] are a set of six metals that sit in the middle of the periodic table: ruthenium, rhodium, palladium, osmium, iridium and platinum. PGEs are siderophile elements, meaning they are 'iron-loving' , as opposed to lithophile elements which are 'rock-loving', hence they combine easily with oxygen. The PGEs' affinity for iron means that, when the Earth formed, they tended to preferentially gravitate towards the Earth's core because it is itself made mostly of iron."

Natalie Starkey

Starkey, N. (2018). Catching Stardust. Comets, asteroids and the birth of the solar system. Bloomsbury Sigma.

[* I was not entirely sure how to classify this explanation, but it is clearly a pseudo-explanation as it stands, as it suggests platinum group elements migrate to the centre of the earth because they like iron and that is where a lot of iron is to be found. At the very least, there is something important missing from the explanation as it is not scientific as provided.]

Read about teleology in science

Read examples of teleological (pseudo)explanations for scientific phenomena

Read about types of pseudo-explanations

Author: Keith

Former school and college science teacher, teacher educator, research supervisor, and research methods lecturer. Emeritus Professor of Science Education at the University of Cambridge.