History Of Animal Life On Earth Flashcards
It gives us the bulk of insights into history of life and cam be completed remains, fragments of hard parts, or traces
Fossil record
It measures the decay of radioactive elements in igneous rocks
Radiometric dating
What is commonly used for dating bio materials less than 75,000 years old?
Carbon-14
What was used before radiometric dating to identify the geological time scale?
Strata
What are the 3 limitations of the fossil record?
- Some time periods are not properly represented
- Small amount of fossils recovered
- Biased towards more abundant and widespread species
True or false: fossil records still allow us to understand how biodiversity changed over time
True
What uses genetic data from different organisms to generate branching trees that represent hypotheses of how different organisms are related?
Molecular data
What hypothesis states that DNA and protein sequences evolve at a relatively constant rate?
Molecular clock hypothesis
Why do molecular and fossil evidence not always agree?
They provide different estimates for the dates of origins for specific groups
What period in The Precambrian did the genetic toolkit of animals evolved?
Ediacaran period
What was the genetic toolkit in the Ediacaran period based on?
Similarities between animals and choanoflagellates
What rapid diversification of life happened in the Paleozoic?
Cambrian explosion
How long did the Cambrian explosion last? And what first appeared?
20 million years; Modern phyla
Three possible causes of the Cambrian explosion
- Increase in atmospheric oxygen
- Evolution of new gene regulation mechanisms
- New inter species interactions led to more evolution
Describe the earliest true vertebrates that diversified during the Cambrian
Chordates were jawless fish with bony armor
Describe what first appeared during the Silurian
Gnathostomes are vertebrates with jaws and paired limbs
What were the first terrestrial animals?
Arthropods
What preceded before terrestrial animal evolution?
Terrestrial plant evolution
What evolved during the Carboniferous and reached gigantic size?
Winged insects; Arthropods
The first terrestrial vertebrates evolved from?
Lobe-finned fishes: Tiktaalik
What tetrapods diversified in the Carboniferous?
Amniotes
What are the two groups of Amniotes?
- Sauropsids
- Synapsids
What amniote was the lineage of reptiles and birds?
Sauropsids
What amniote was the lineage if therapsids and mammals?
Synapsids
What is a widespread and rapid loss of biodiversity over a short period of time where species are lost faster than they can be replaced?
Mass extinction
What was the first major mass extinction that happened 443 MYA and killed 85% of species?
Ordovician-Silurian ME
What was the second major mass extinction that happened 374 MYA and killed 75% of species?
Devonian ME
What was the third major mass extinction that was the largest and happened 250 MYA where 95% if species were killed and caused by a large volcanic eruption in Serbia?
Permian ME
What was the fourth major mass extinction that happened 200 MYA and killed 80% of species?
Triassic ME
What is the fifth major mass extinction that killed 78% of species caused by an asteroid, lowering global temperatures?
Certaceous-Palogene ME
What was the Mesozoic often called as?
Age of Reptiles
Why did predation escalate during the Mesozoic?
Evolutionary arms race: predator and prey coevolve
What sauropsids consisted of lizards, snakes evolving from lizards, and tuaturas
Lepidosaurs
What sauropsid consisted of crocodiles, dinosaurs and birds? Where crocodiles and birds are the only surviving?
Archosaurs
What first appeared in the late Triassic and has 2 major groups?
Dinosaurs
What dinosaur is lizard-hipped, herbivorous with specialized teeth such as triceratops?
Ornithischian
What dinosaurs is bird-hipped and has 2 major groups?
Saurichia
What saurichia is a large herbivore with small heads and long necks such as Brachiosaurus?
Sauropods
What saurichia is bipedal, mostly carnivorous such as Velociraptor?
Theropods
What emerged from small theropod ancestors; Archaeopteryx
Birds
In the Cenozoic, how long did it take for Marine animal diversity to recover?
10 million years
True or false: modern plant and animal families emerged and birds and mammals proliferated in the absence of non avian dinosaurs
True
Yes or no: was the rate if mammal diversification increased after the extinction of dinosaurs? Why?
No because extinct mammal groups coexisted with dinosaurs
What were the three of many mammal groups that appeared in the Cenozoic?
- Rodentia
- Cetacea
- Carnivora
What were apes separated by and how long?
Homo sapiens; 7 million years
Where did the origins of the hominin and hominin evolution occur?
Africa
What hominin has very similar anatomy and behavior with modern humans and first to leave africa?
Homo erectus
What hominin appeared in Africa 200,000 years ago?
Homo sapiens
When did humans spread out of Africa?
60,000 years ago
What was the last epoch before the modern day?
Pleistocene
What happened in the Pleistocene epoch?
Global temperatures dropped creating land bridges for animals to move freely
What extinction occurred at the end of the Pleistocene and into the Holocene?
Megafaunal extinction
What was the sixth major extinction caused by Homo Sapiens since the Industrial revolution, putting pressure on natural world through unsustainable resource use?
Holocene ME
What 4 factors drive the Holocene ME?
- Climate change
- Habitat destruction
- Unsustainable resource use
- Hunting
How long till the next massive extinction?
240-540 years
