an emergent
website design
by
peter jay stein, md, ma
atmosphere
asthenosphere
lithosphere
regolith
biosphere
hydrosphere
This 54 page synopsis of the evolution
of the Earth, the origin and progression of life, and the
emergence of humans as descendants of the hominin lineage, divides the last 4.57 billion years into progressively overlapping, imagistic, time segments, to outline our place in biological existence.
magnetosphere
ionosphere
THIRTEEN
Emergent Animals I
adapted from Biology, 10th Edition, 2015, pp. 533, 625
PROKARYOTES
PROTISTS
EUKARYOTES
CHOANOFLAGELLATE ANCESTOR
BACTERIA
ARCHAEA
FUNGI
CHOANOFLAGGELATES
THE FIRST ANIMAL!
-no distinct nuclei
-no other membranous organelles
-asexual reproduction by binary fission
-have membrane-enclosed organelles
(nucleus, mitochondria, plastids)
-multiple chromosomes of DNA and proteins
-sexual reproduction
-mitosis and meiosis
-ancestor to 2 clades: unikonts and bikonts
-a paraphyletic group (definition, below)
-Kingdom 'Protista' no longer a clade
-the first eukaryotes to evolve
-unicellular, multicellular, and simple, multicellular organisms
-includes algae, water molds, and protozoa
-
THE COMMON ANCESTOR OF ALL ANIMALS
-
CELLS BECOME SPECIALIZED TO PERFORM SPECIFIC FUNCTIONS
unikont
bikont
(clade)
(clade)
(2 flagella)
-
a single, posterior flagellum
opisthokont
amoebozoa