Can You Spot The "Sixth Extinction"?

For an original post on the "Sixth Extinction," see this link. 

 

Extinction intensity, without labels, link here, can you spot the "Sixth Extinction"?

Extinction intensity, with labels, link here, "H" designates the "Sixth Extinction":

Periods across the top, starting with the Permian Period:

• Permian Period
• by the early Permian, the two great continents of the Paleozoic, Gondwana and Euramerica, had collided to form the supercontinent Pangaea. Pangaea was shaped like a thickened letter “C.” The top curve of the “C” consisted of landmasses that would later become modern Europe and Asia.
• Triassic Period -- one continent
• Jurassic Period -- one continent
  
• [K]retaceous Period -- two continents
  
• Paleogene Period
• Paleocene Epoch
• Eocene Epoch
• Oligocene Epoch
  
• Neogene Period
• Miocene Epoch
  
• Pliocene Epoch
• Quaternary Period (not seen/labeled): cyclic growth and decay of continental ice sheets
  
• Pleistocene Epoch -- Ice Age
  
• Holocene Epoch -- Ice Age receded
  

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Etymology

-cene: from the Greek kainós, latinized as cænus, new;

Pliocene (thought to be "last" layer to contain fossils):

• Lyell originally thought this to be the youngest fossil rock layer (first layer in which fossils would be found)
• plio: Greek -- more, "more new"

Pleistocene (later, discovered to also have fossils)

• pleisto: Greek -- most, "most new" when it was realized that one could find fossils in a a more recent layer, or the "most new" layer with regard to fossils
• extends to the modern time
• colloquially referred to as the Ice Age
• 2.6 mya to 11,700 ya
• as of 2009; prior to 2009, 1.8 mya to 11,700 ya; 
• so in 2009, the Pleistocene was extended almost one million year
  
• spans the world's most recent period of repeated glaciations
• continents in “today’s” positions

Holocene:

• -holos: Greek -- whole
• kainos: new
• thus, "whole new" or "entirely new" -- but think "H" for human

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Extinctions Defining Divisions

This is interesting. When one looks at the mass extinctions in the second of two graphics above, it is notable that the three major extinctions "defined" three periods: the Permian Period, The Triassic Period, and the [K]retaceous period. 

It is noteworthy that a singular division, the division between the Jurassic and the [K]retaceous is not identified.

The Jurassic Period ended 145 mya and there appears to be a minor extinction spike about 150 mya which might coincide with a J-K event. What happened at the J-K event? Apparently not much in the way of extinctions.

However, during the Jurassic, the world broke into two continents:In the Jurassic, both plant-eating and meat-eating dinosaurs grew enormous -- and, thus, Jurassic Park. The world broke into two continents.

In the Cretaceous, flowering plants and many insects evolved. Duck-billed dinosaurs and horned dinosaurs developed.