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- Jul 29, 2022
- 4 min read

Fossil Friday: There are Many Different Kinds of Fossils! Part 2

Quiz (answers to the quiz are at then end of this blog post)

1) The oldest fossil of any gecko was found encased in amber. This fossil showed in detail

that geckos evolved the ability to_____________________ much earlier than expected.

a) Capture prey with a long sticky tongue

b) Walk upside down on ceilings

c) Blend into their environment through camouflage

d) Lose their tail (and regrow it later) to escape predators

2) Evidence for the existence of "Angiosperms", plants the require male and female cells

for reproduction, was found in a piece of amber that formed:

a) 5 million years ago

b) 20 million years ago

c) 75 million years ago

d) 100 million years ago

"More on Preserved Fossils-And then there was AMBER!"

By Synthia Durrant

In the previous post, we learned that fossils found in ice and permafrost are often preserved in such good condition they look as though the animal or organism might be sleeping. Today we are learning about fossils that have been discovered in amber. Amber is tree resin that has achieved a stable state through the loss of volatile constituents (1). This means amber won't decompose or break down under normal conditions; it has become "stable".

Some trees secrete a sticky sap that has the right chemical composition to stabilize and slowly turn into amber (fossilized tree resin) which is a form of polymer. Tree resin that has turned into amber is "fossilized". A polymer can be thought of as a natural form of plastic. Small animals, microorganisms, insects, and plants that get trapped inside the sticky sap will also turn into fossils along with the resin (1) (A).

About 5% of the time, amber is found with inclusions. Inclusions are anything that got stuck inside the resin before it hardened; sometimes inclusions are just pieces of dirt or debris, but other times inclusions can be parts of or even entire organisms that were encased and preserved at the exact moment they were covered. The resin acted in a similar way as a plastic casing, protecting the inclusions through millions of years and depositing them as intact specimens ready for today's paleontologists to study. While many scientist dispute the notion that whole genes could be removed from these organism to recreate them as is depicted in the Jurassic Park series, after viewing some of the amazing fossils that have been found in amber, it is easy to understand why a fiction writer could weave a tale where it is possible.

A) Cyanobacteria B) Slime Mold C) Wasp D) Leaf E) Remains of a feather F) Aspergillus-type fungus (B)

Many of these fossils look like they became trapped only yesterday, some even look like you cold reach in and rescue them from their demise! One of these unfortunate creatures is a salamander-like amphibian that fell into tree sap that eventually developed into amber from the Eocene Era (from 56 to 33.9 Million Years Ago (MYA)). This piece of amber was discovered in the Baltic region of Europe (3) (4).

A small amphibian became trapped in amber during the Eocene Era (56 - 39.9 Million Years Ago--MYA). This salamander-like creature appears to be struggling to swim it's way out of the amber. It is an extraordinary find (B).

Occasionally, fossils trapped in amber provide us with a glimpse of their world, the real life struggle of life and death between organisms that existed eons before we can even imagine.

A young spider was just about to make this wasp it's meal as they were both covered in tree sap. This epic struggle for life and death was captured from the Early Cretaceous Period in what is now modern day Myanmar (C).

This piece of amber (above) found in modern day Myanmar shows the moment, frozen in time, that a spider pounced on a wasp. As the spider was maneuvering for a death blow, both were instantly encased in tree sap, gripped forever in their battle for life and death! This snap-shot was captured 97 to 110 MYA in the early Cretaceous Period (5). It is incredible that amber was able to capture that specific moment, and even more amazing that someone found the amber and shared it with the world 100 million years later.

This perfectly preserved praying mantis was discovered in Dominican Republic and is thought to be 23-33.9 million years old (E).

This insect (above) from the Oligocene Era (23-33.9 MYA) is unmistakably a mantid and looks amazingly similar to modern mantids. See a comparison (below):

The image on the left is a modern, living mantis (F). The image on the right is a close up of the mantis preserved in amber at least 23 MYA (above) (E).

Fossils preserved in amber can be an extraordinary insight into the lives of creatures that existed millions of years ago. They are literally moments captured in time that bring the past to us exactly as it was. No other fossil type has the ability to capture our emotions the way amber fossils do.

Quiz Answers:

1) The oldest fossil of any gecko ever found showed in detail that geckos evolved the ability to_____________________ much earlier than expected.

b) Walk upside down on ceilings (6)

The oldest fossil ever found of a gecko dates back to 100 MYA. The amber preservation was so perfect that the “lamellae,” or the sticky toe hairs, that allow geckos to walk up walls and upside down across ceilings can be clearly seen through the amber (6) (G).

2) Evidence for the existence of Angiosperms, plants the require male and female cells

for reproduction, was found in a piece of amber that formed:

d) 100 million years ago--The following quotation is from a press release given by

Oregon State University regarding the stunning quality of the amber fossil they are

referring to:

"In Cretaceous flowers we've never before seen a fossil that shows the pollen tube actually entering the stigma," George Poinar jr. said in the press release. "This is the beauty of amber fossils. They are preserved so rapidly after entering the resin that structures such as pollen grains and tubes can be detected with a microscope." (7)

Cretaceous Era flowers preserved in amber show sexual reproduction in plants was occurring 100 MYA. Plants that require male and female cells for fertilization and reproduction are called "angiosperms". Now scientists know their existence is concurrent with dinosaurs (H).

Definitions:

. amber-a naturally occurring polymer that is stable

angiosperms-plants that require male and female cells for fertilization &

reproduction

diurnal-having a wake period twice during a 24 hour day

geckos-these are diurnal and nocturnal lizards that evolved sticky hairs on their

feet allowing them to walk up vertical structures and upside down across

horizontal structures (most geckos have this feature, but not all) (8)

inclusion-anything stuck inside of amber (this word can also refer to any thing stuck

inside of gemstones & crystals)

nocturnal-having a wake period during nighttime hours

polymer-translates from greek as "many parts", it refers to long chains of substances