Moss Flashcards
How did Evolution affect culture
Evolution as an idea spelled the end of the world as we once knew it
It disrupted all religious creation myths that were deeply embedded in culture.
And its all the fault of 5 british scientists
what was James Hutton idea
His idea = uniformitarianism, makes the assumption that natural processes in the universe are the same everywhere and throughout time
His theory of slow processes overturned the dominant idea that most of what we saw was due to short-lived catastrophic events.
who was James Hutton
James Hutton (1726-1797)
a well educated scot who put forward the idea that previous animals and plants were found in ancient sediments laid fown by the sea came from fossils that he uncovered as he was clearing parts of his farm.
In scotland modern layers of sediment lay on top of old red sandstone from the devonian, which is on top of older layers from the Silurian.
who was Charles Lyell
Charles Lyell (1797-1875)
Thought up the geological principle of actualism i.e. geological actions today are the same as those in the past
principle behind paleoecology, the study of ancient extinct ecosystems.
Hutton and Lyell reset the age of the earth from thousands of years old to millions of years.
who was Mary Anning
Mary Anning (1799-1847)
greatest fossil collector of her age
discovered the first complete icthyosaur at age 12
first intact pleiosaur at 25
and Dimorphodon Macryonx at 29
her dog died :(
selled sea shells by the seashore
her friend painted the first aquarium view piece of paleoart to support her living
who discovered evolution
Charles Darwin (1809-1882) and Alfred Russel Wallace (1823-1913)
both independently thought up the theory of evolution.
1858
summarize the history of evolution as an idea
- Hutton and Lyell discovered deep time in geology
- Anning collected, cleaned, and sold fossils from the past
- Victorians were excited by and open to the prospect of fossil discoveries and, became inclined to consider alternative explanations of the origins and evolution of life.
- Although the interpretation of geological evidence was presented as common sense, the theories and ideas began to develop, such as evolution, challenged traditional beliefs.
where did plants come from
Plants = Ebryophytes
which are descended from algae
what unifies plants
Plants are unified by four features
- production of gametes from gametangia
- eggs from archegonia
- sperm from antheridia
- multicellular embryos
- spores with walls
- growth by apical meristems
the last three are features adapted to life on land
how can mosses survive water loss
Mosses are able to lose much of their water
They can do this because mosses are poikilohydric (they lose water freely)
to avoid desiccation, they trap external water
they also have a physiological trick - mosses and moss piglets insert sugars into their membranes and, turn their membranes into an oxygen-excluding glass.
Many moss species can resurrect from complete desiccation.
what are mosses
the first group to branch off of the plant family tree, before early vascular plants
The moss gametophyte is fastened to substrate by small hairs called rhizoids that absorb nutrients. Not specifically for water absorption, as the name little root (rhizoid) implies. All parts of the gametophyte absorb water
what happened to Mary Anning in the 20th century
Mary Anning during the 20th century was largely pushed to the side of the story of evolution.
Then Evie Swine as a 10 year old helped bring her back to popularity. (around 7 years ago)
What is Poikilohydry
> Poikilohydry = lack of ability to maintain and or regulate water content to achieve homeostasis of cells and tissues connected with quick equilibration of cell/tissue water content to that of the environment
Means that they don’t self regulate water content and use the environment.
Will dry out in dehydrated times, then refill when it rains.
what happens if you slice up moss
Mosses can survive being fragmented into many pieces and recover as multiple new mosses.
how do mosses survive desiccation
Mosses lose water freely but trap external water to avoid desiccation.
if they do desicate, they:
- insert sugars into membranes, turning them to oxygen excluding glass
- specialized proteins protect the DNA from stresses
Moss and water bears (moss piglets) (tardigrades) can recover from complete dessication.
