AFTER welcoming three new members to Teignmouth Probus Club, Roger Avery, a zoology lecturer at Exeter University, explained to members that about a billion years ago, first life started developing into plants synthesising sunlight, producing oxygen, writes Rick Purnell.

Then came animals which fed on plants, then animals which fed on other animals. Because of uneven climates, from heat to cold from wet to dry, species adapted in enormous varieties in the first 800,000 years. Not a lot happened since except the emergence on man, hunter gatherer then settled in agriculture some 50,000 to 100,000 years ago.

Each separate land mass prospered its own life forms as evidenced by those locations with minimal human intervention such as Australia (kangaroos), New Zealand (kiwis), Madagascar (lemur) Galapagos (several species).

Human exploration and migration particularly by boat carried many ‘stowaways’ to foreign parts. Brown rats now found throughout the world almost wherever man has been. This was so long ago, there is no way of tracing their origin. Much of our flora and fauna is alien to our shores. Daddy longleg spiders come from South West European caves. Grey squirrels ‘tree rats’ from North America in 1870s, imported as park animals. Gib-leaved Toadflax and roadside Alexanders came with the Romans, Normans brought in pheasants from North-west Asia, and then the ubiquitous wall daisy from Central America. There is currently ‘war’ on Japanese knotweed. Barnacles are not native and only came in from Australia when the Suez Canal opened.

Aliens about to arrive in Devon in the next 20 years or so will be the New Zealand flatworm, bad news for gardeners as it decimates earthworms. Ring-necked parakeets from Tropical Africa will be commonplace in our trees.

Extinctions occur all the time, the next to disappear at our latitude will be the native bluebell, they will move northwards as they are currently at their most southerly point for survival and will either be overcome with increased temperatures (global warming) or pollen swamping from the Iberian (Spanish) Bluebell.

The talk was not about little green men after all! Vote of thanks was given by Tom Haynes.

With the Covid-19 global emergency, Probus meetings have been suspended and will be reviewed again at the end of April. For updated news please visit our website: http://www.teignmouth-probus-club.org.uk