Sunday, March 24, 2024

Polyploidy Part 3. Patterns in Nature: Speciation

 Polyploidy is whole genome duplication, when all the chromosomes and so, all the genes, of an organism double. In plants, it is very common; easily 3/4 of plants are polyploid. 

Oenothera, evening primrose
an Oenothera

Because polyploidy is a genetic effect that takes place inside the cell's nucleus, it is not casually observed. But botanists discovered polyploidy as soon as they had microscopes to look at the contents of the nucleus and when they tried crossing polyploids and got results that didn't make sense based on diploid genetics. (Diploid = 2 copies of the genome, polyploidy = numbers over 2, like 3, 4, and 6  see previous posts in this series link link). Study of polyploidy began in the early 1900s.

Sunday, March 17, 2024

Plant Story--Catnip, Nepeta cataria, a Well-Known Weedy Herb

 Catnip, Nepeta cataria, is one of the better-known little herbs because it is a drug for cats. Cats respond to catnip for about 15 minutes, with distinctive behaviors from rubbing on their faces and rolling in it to grooming and salivating. Young kittens do not respond and some adult cats never do. On the other hand, the response is widespread among cats of all kinds, lions, tigers, cheetahs, lynx, pumas and so on, but not dogs or rabbits or rats or other groups of animals. Since cats are common pets, people provide or grow catnip for them, with the result that catnip is known to many people.

catnip, Nepeta cataria
catnip, Nepeta cataria

Sunday, March 10, 2024

April in Tokyo

Here is a photo album of pictures from Tokyo in April. Beautiful spring flowers.

The photos are from April 2017 but if you hurry, you could still get there to see what it is like in 2024: 

Classical Japanese design

garden, Tokyo

Sunday, March 3, 2024

Polyploidy Part 2. And Crop Plants

Polyploidy is whole genome duplication, where all the chromosomes double. Animals rarely survive major chromosome changes, but plants usually do, leading to aspects of plant genetics that are quite different from animals. 

strawberry, Fragaria ananassa
strawberry, Fragaria ananassa

Even though you cannot easily spot a polyploid by looking at it, polyploidy is not obscure. Many common, important plants are polyploid, for example bread wheat (Triticum aestivum), white potatoes (Solanum tuberosum), coffee (Coffea arabica), sweet potatoes (Ipomoea batatas), strawberries (Fragaria x ananassa) and cotton (Gossypium tomentosum). Researchers estimate that 75% of all plants, and likewise, 75% of crops, are polyploids.