Friday, April 13, 2018

Species diversity (4/13/2018)

I am reading an interesting book, in it the author discusses how by the end of the 1700 people started doubting the creation story in the bible.  By that time, explorers and naturalists had fanned out all over the world and the sheer number of different species blew them away.  For example, the Duchess of Portland, Margaret Bentinc was a species collector and purchased samples from naturalists who returned from their exploratory travels. At her death she had thousands of species.  It seems that the auction of her collection in 1785 lasted 38 days.

It was therefore no surprise that around the 1800, people were starting to wonder how all these species could have fit on Noah's arc, let alone travel from all over the world to get there on time.  You get the message.  In a way, this together with what they found in the fossil record made them ready for a person like Charles Darwin.

No, I don't want to argue evolution in this post, but just the diversity of species in the woods behind my home. Although, I could talk about evolution to some extent since one of the plants back there is running cedar or ground pine (Diphasiastrum digitatum).  This plant is actually considered one of the older species alive in our area.  It was most likely here when the dinosaurs were roaming around.  How do we know?  Well, it is in our fossil record.   In addition, it has a very primitive way of sexually reproducing.  It actually produces spores (that used to be collected for use as flash powder) that, once they fell on the soil, grew subterranean and developed male and female parts.  The male parts would release a sperm cell with a tail and swim to the female part to fertilize it.  The sperm cell could only do that when it and the female part were submerged in water or had a water drop on it.  Only after fertilization did you get a plant that emerged out of the ground.  

That is pretty primitive isn't it?  Later on in evolutionary time, plants found a much more efficient way of doing this which was to produce pollen and make us all sneeze.  Only us animals never figured a better way to do it.  Or, maybe we did ... the male animals developed an organ (a.k.a. penis) to deposit the sperm cell pretty darn close to the egg cell or at least in an environment where it is nice, warm and wet and thus easy swimming for those little guys; no rain drops needed.

Running cedar is not the only evolutionary old plant in the woods behind our home.  Ferns are also among the oldest species, and actually they breed the same way as running cedar, through spores.  A minor exception is that their spores turn into moss and a lot of the moss we see is actually ferns that are waiting for the correct moment to get fertilized and become real ferns.  They all have the male and female parts and if a water drop (or more) would straddle a male and female sexual organ a sperm cell would also swim over and kaboom, we would get a new baby fern plant growing right in the middle of the moss.  This has happened in my bonsai pots, to my frustration, where I thought I had a nice moss carpet.  I also saw it on a bonsai channel I was watching on YouTube.  

Botanists have therefore lumped the ferns and the running cedars into one group called the Pteridophytes or plants that reproduce via spores.  Walking behind our home I often see Christmas fern, royal fern, cinnamon fern, New York Fern, lady fern and sensitive fern (6 different species). 

I think this is enough species diversity for one post, the Pteridophytes in the woods behind our home.  But just a quick update on a previous post.  The pines are in full bloom (if you are allowed to call it that).  There is pine pollen everywhere.  This means it is about on time or maybe a few days earlier than other years, even though we had a cold March.  Something to think about.  Not sure what other group of plants I'll write about next, (maybe the conifers) stay tuned!
It is pine pollen season alright (photo taken on 4/13/2018).  On my Instagram account I called it ring around the collar.  
  





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