Continental drift plate tectonics theory. In particular, the English geologist Arthur Holmes proposed in 1920 that plate junctions might lie beneath the sea, and in 1928 that convection currents within the mantle might be the driving force. Holmes' views were particularly influential: in his bestselling textbook, "Principles of Physical Geology," he included a chapter on continental drift, proposing that Earth's mantle contained convection cells which dissipated radioactive heat and moved the crust at the surface. Holmes' proposal resolved the phase disequilibrium objection (the underlying fluid was kept from solidifying by radioactive heating from the core). However, scientific communication in the '30 and
Drift seed Drift seed Drift seeds (also sea beans) and drift fruits are seeds and fruits adapted for long distance dispersal by water. Most are produced by tropical trees, and they can be found on distant beaches after drifting thousands of miles through ocean currents. This method of propagation has helped many species of plant such as the Coconut colonize and establish themselves on previously barren islands. Consequently, drift seeds and fruits are of interest to scientists who study these currents. In botanical terminology, a drift fruit is a kind of diaspore, and drift seeds and fruits are disseminules. Enthusiasts founded an