Down To Jupiter

Poul Anderson, Three Worlds To Conquer, Chapter 15.

Anticlimax: Theor is back down on the Jovian surface. However, his trip through the sky has served its purpose. We have been given an overview not of history but of evolution:

life probably began at high altitudes;

Nyarrans and Ulunt-Khazul are different species of the same genus whereas the Hidden Folk are not even of the same phylum;

their common ancestor was an animalcule.

Theor is now in a forest of thick-boled yorwar trees with hollow upward-floating branches and lung-like leafs that build complex molecules out of methane and ammonia, releasing hydrogen. This photosynthesis, dependent on synchroton radiation, lightning and the sun, requires maximized internal surface. The trees are low but many.

Rocks, comprising water crystallized with silicon and magnesium compounds, shatter like obsidian, providing Theor with a coup de poing and spearheads. With the hand-ax, he makes a shaft from a larrik bush and secures one of the points with fibers from the plant. Then he follows the track of a skalpad, a large, shelled, six-legged animal, drives his spear first into its throat pouch, then into an eye, finally killing the animal with repeated blows from the ax. He wants both its meat to eat raw - Jovians do not yet cook much - and its shell for another purpose.