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The Tree of Life

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Marion Cagnard

on 19 April 2016

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Transcript of The Tree of Life

By: Marion Cagnard, Kaush Gokul, Noah Wick
The Tree of Life


Importance to Humans:
Niches and Ecological Roles:
Interesting Facts:
Prokaryotic unicellular cells that reproduce by binary fission and come in the forms spirilla, bacilli, or cocci. Some also have cell walls made of peptidoglycan.
- Bacteria are able to be parasitic and harm humans, so a knowledge of them is needed to keep humans safe
- Bacteria help in the digestion systems of many animals
- Bacteria are used in modern day medicines
- Bacteria have the potential to carry genetic information through plasmids for human gene therapy
- Bacteria can be used gastronomically in foods eaten by humans
-Bacteria are used to clean oils out of the ocean and to breakdown pollution
1) there are more bacteria in a person's mouth than people in the world
2) bacteria can be killed with antibiotics
3) most harmful bacteria can be killed at high heats
4) some bacteria can produce oxygen
5) some bacteria can live in radioactive environments
6) the prokaryotic bacteria reproduce by binary fission

Purple Bacteria
- Perform photosynthesis without producing oxygen
- Have flagella
- Use non-water molecules to get electrons for photosynthesis
- Conduct nitrogen-fixation which is vital for plants
Chemoautotophic Proteobacteria
They are very diverse. They can be terrestrial or aquatic, sexually reproducing or asexually reproducing, and unicellular or multicellular.
They commonly produce basidia (cells on which sexual spores are produced) and dikaryon where the cell in the thallus contains two haploid nuclei.
They also have clamp connects or outgrowths which are specific to some Basidiomycota.
They all have an ascus in which nuclear fusion and meiosis takes place.
They have the same cell wall that is characteristic of many fungi.
Obligate sybiotes
Formation of arbuscules in plant roots
Large, multinucleate spores with layered walls
Non-septate hyphae
Able to grow within plant roots without causing a disease
They are unique because they have motile stages in their life cycles. No other fungi have this trait.
They live in permanently or temporarily aquatic habitats.
Structurally, they are fairly simple.
These fungi are anaerobic
They have hydrogenosomes instead of mitochondria which are adapted to the oxygenless environment

A parasitic unit made of a protein coat containing either DNA or RNA. Many viruses also contain an outer membrane that they receive when exiting a host cell.
Phylogenetic Relationships
Viruses are not alive because they do not do many of the things needed for an organism to be considered living. For example, a virus cannot reproduce without the help of a host's cells organelles because a virus does not have organelles or ribosomes of its own. The most significant feature that doesn't make a virus alive is that it is not composed of cells, the smallest unit of life.
Because viruses are not alive, they do not have a phylogenetic relationship with any organism on the tree of life.
Importance to Humans
Although some viruses can be used to treat diseases and have their vectors used for genetic engineering, most are harmful to humans because of their parasitic nature. These harmful aspects include:

Cause many diseases
Biological warfare
Damage to livestock and crops that are used as food sources

Niches/ Ecological Roles
Interesting Facts:
1) Viruses aren’t alive
2) Viruses are about 20-250 nanometers big
3) Outbreaks of certain viruses have killed more people than world wars
4) The common cold is caused by a virus
5) Viral genetic information can be encoded in either RNA or DNA
6) Many of the most dangerous STDs are caused by viruses
7) Viruses are very difficult to treat because they can hide in a host cell's DNA

HIV (Human Immunodeficiency Virus)
- A retrovirus that uses RNA as its genetic material
- Can be spread sexually or by sharing injection needles
- Scientists are trying to fight HIV with other viruses
Influenza Virus

Tulip mosaic

HPV (Human Papilloma Virus)

Lambda phage


Geobacter Lovleyi
Salmonella Tuphi
Acidothermus Cellulolyticus
Azoarcus Indigens
1) There are a multitude of pathogenic protists.
2) The disease malaria is a protist.
3) The protists were the first eukaryotes.
4) Protist comes from the Greek word protos which means first.
5) Without protists, life would not be able to sustain itself because nutrients would not get recycled.
6) Protists move in a variety of ways including flagella, cilia, and pseudopod


They are all pathogenic and parasitic in a natural environment because they need a host cell to survive and reproduce and in the process, they destroy the cell.
- It is an RNA virus
- There was a large outbreak of influenza in 1918 that killed millions of people
- RNA virus
- Known to cause color-breaking of tulips
- DNA virus
- Often time causes cervical cancer
- DNA virus used as a vector
- known as "bacteria eaters"
Digital image. DPVWeb. N.p., n.d. Web. 11 Mar. 2015.

Flu Virus Microscope. N.d. Success. Web. <http: successimg.com/flu-virus-microscope/>.

"HIV: Fighting Virus with Virus." HIV: Fighting Virus with Virus. N.p., n.d. Web. 11 Mar. 2015.

"Intralytix, Inc. - News." Intralytix, Inc. - News. N.p., n.d. Web. 11 Mar. 2015. <http://

"Introduction to Plant Viruses." Introduction to Plant Viruses. N.p., n.d. Web. 11 Mar. 2015.

N.p., n.d. Web. <http%3A%2F%2Fen.citizendium.org%2Fwiki%2FBacteriophage>.

"MicrobeWorld." Viruses. N.p., n.d. Web. 11 Mar. 2015. <http://www.microbeworld.org/types-

"Introduction to the Viruses." Introduction to the Viruses. N.p., n.d. Web. 07 Mar. 2015.
- Viruses that infect plants
- RNA virus
In the natural world, bacteria are responsible for:

- nitrogen fixation: bacteria are able to take inorganic molecules and make them into compounds such as ammonium that plants can use
- bioremediation: stimulates the breakdown of pollutants
- natural recycler: decompose other organisms to obtain energy
Importance to Humans

-Some protists like seaweed can serve as food.
-They decompose/recycle nutrients.
-They perform photosynthesis and provide energy to the rest of the ecosystem.
-By performing photosynthesis, they also replenish the atmosphere with oxygen which is essential for human survival.
-Some are pathogenic and can cause damage to crops and humans.
-Some protists produce harmful toxins which can accumulate in coastal areas.
Eukaryotic organisms which are not plants, animals, or fungi. Many are unicellular except for a few algae. They are grouped into groups called fungus-like, plant-like, and animal like.
Niches/Ecological Roles
- Produce a lot of oxygen (algae)
- Decompose some organisms to
- May be parasitic to certain organisms
- Are found almost everywhere in the world
Interesting Facts
A group consisting of largely multicellular organisms which play an important role in the web of life.
-All fungi are non-motile meaning that they do not move.
-Can go through either sexual or asexual reproduction.
-They are heterotrophic.
-Haploid thalli offspring are the result of zygotic mitosis.
-The exterior structure is primarily composed of chitin and alpha-glucans.
-There are a few exceptions to these shared characteristics as some fungi have cellulose in their cell walls and some others have flagella for movement. It has also been shown that some fungi can be diploid even though the majority are haploid.
Synapomorphies (Shared Derived Characteristics)
Importance to Humans
-They provide of variety of foods and beverages for humans like bread and alcohol.
-Some can be used to produce cheeses and the mushrooms of others can be eaten.
-Fungi have an important role in medicine. For example, penicillin is based off of natural chemicals derived from fungi.
-As far and science and industry is concerned, some fungi are being used to create more environmentally friendly structural materials.
-They help decompose organic matter in the environment.
-They are vital to plants because they facilitate nutrient and water uptake in the roots.
-Some fungi can be bad; there are a few that are pathogenic towards plants and humans.
Niches/ Ecological Roles
The primary ecological role of fungi is decomposition. Without them, organic matter including essential nutrients would not be recycled and many organisms would die as a result.
Another important task of fungi is helping some plants get the water and nutrients that they need.
Interesting Facts
1) Fungi develop from spores.
2) The visible mushrooms are temporary reproductive structures which protrude from a main body usually hidden in the soil or in/under a piece of decaying wood.
3) Some of the fungal spores are capable of swimming through water.
4) Fungi are more similar to animals than plants.
5) There are over 1.5 million species of fungi.
6) One single specimen in Oregen is over 2.4 miles in area.
Paramecium aurelia
Euglena gracilis
Plasmodium falciparum
Rozella allomycis
- Parasitic water mold that live in aquatic/marine habitats.
- conducts nitrogen fixation which is vital for plants
- Autotrophic (self nourishing)
- They survive without carbon
- aerobic bacteria
- gram positive
- non-motile
-Aerobic bacteria
- Gram negative
- growth mediums are nutrient broth and nutrient agar
- anaerobic
- gram negative
- grows in dsmz medium 732
- gram negative bacteria
- anaerobe
- produces no gas when grown in TSI media
Rozella. Digital image. TOLWeb. N.p., n.d. Web. 12 Mar. 2015. <http://tolweb.org/tree/ToLimages/rozella1.250a.jpg>.

Digital image. N.p., n.d. Web. 12 Mar. 2015. <http://phylogame.org/classification/basidiomycota/>.

Scarlet Elf Cap. Digital image. N.p., n.d. Web. 12 Mar. 2015. <http://upload.wikimedia.org/wikipedia/commons/6/67/

Glomus Spores. Digital image. N.p., n.d. Web. 12 Mar. 2015. <http://website.nbm-mnb.ca/mycologywebpages/

Allomyces. Digital image. N.p., n.d. Web. 12 Mar. 2015. <http://www.ucmp.berkeley.edu/fungi/allomyces.jpg>.

Digital image. N.p., n.d. Web. 12 Mar. 2015. <http://www.bsu.edu/classes/ruch/msa/wubah/10-2.jpg>.

"Tree of Life Web Project." Tree of Life Web Project. N.p., n.d. Web. 10 Mar. 2015. <http://www.tolweb.org/>.

N.p., n.d. Web. <http%3A%2F%2Fgenomehttp%3A%2F%2Fgenome.jgi.doe.
Paramecium Aurelia. Digital image. N.p., n.d. Web.
12 Mar. 2015. <http://www.nature-education.org/paramecium-aurelia.gif>.

Euglena Gracilis. Digital image. N.p., n.d. Web.
12 Mar. 2015. <http://www.dr-ralf-wagner.de/Bilder/Euglena_gracilis.jpg>.

Amoeba Feeding. Digital image.
Http://www.microscopy-uk.org.uk/mag/imagsmall/amoebafeeding3.jpg. N.p., n.d. Web. 12 Mar. 2015.

Plasmodium Falciparum. Digital image. N.p., n.d. Web.
12 Mar. 2015. <http://upload.wikimedia.org/wikipedia/commons/f/fc/Plasmodium_falciparum_01.png>.

Diatoms. Digital image. N.p., n.d. Web. 12 Mar. 2015.

Slime Mold. Digital image. N.p., n.d. Web. 12 Mar. 2015.
"Acidothermus Cellulolyticus." Acidothermus Cellulolyticus. N.p., n.d. Web. 12 Mar. 2015. <http://www.thelabrat.com/protocols/Bacterialspecies/Acidothermuscellulolyticus.shtml>.

"Eubacteria." Eubacteria. N.p., n.d. Web. 12 Mar. 2015. <http://faculty.college-prep.org/~bernie/sciproject/project/Kingdoms/Bacteria3/eubacteria.htm>.

"Facts About Bacteria and Viruses." Facts About Bacteria and Viruses. N.p., n.d. Web. 12 Mar. 2015. <http://www.scienceprojectideas.co.uk/facts-about-bacteria-viruses.html>.

"The Importance of Bacteria to Humans." Encyclopedia Britannica Online. Encyclopedia Britannica, n.d. Web. 12 Mar. 2015. <http://www.britannica.com/EBchecked/topic/48203/bacteria/272367/The-importance-of-bacteria-to-humans>.

"Tree of Life Web Project." Tree of Life Web Project. N.p., n.d. Web. 10 Mar. 2015. <http://www.tolweb.org/>.
Known for the many cilia they have
Move using flagella
Have an eyespot
Have chloroplasts
Can also organisms for food
Causes Malaria in humans
Parasitic Organism
Invades liver of host
Physarum polycephalum
Move/get food with pseudopods
Asexually Reproduce
Have silica shells
Basis for marine food chain
Consumes bacteria and fungal spores
Goes into reproductive cycle if no food nearby
All members have a nucleus, membrane-bound organelles and a cytoskeleton. They can be unicellular or multicellular and can reproduce either sexually or asexually.
- Ovules enclosed by a carpel
- Double fertilization -> leads to endosperm
- Stamens with two pairs of pollen sacs
- Features of gametophyte structure and development
- Phloem tissues consist of sieve tubes and companion cells

Angiosperms are likely the most important of phyla of plants to humans. They produce such a great variety of materials that benefit humans. They produce fruit, building supplies, and largely provide food for animals. In addition to these, they also produce oxygen through photosynthesis. It’s hard to see how humans would be able to live without angiosperms
Importance to Humans
Niches/ Ecological Roles
By using pollen and flowers as reproductive methods, angiosperms formed the niche of using flying insects and bird as a method to reproduce. They are autotrophs, making them the producers of the foodchain. Many animals rely on angiosperms for food.
Interesting Facts
- There are over 250,000 known angiosperm species
- The oldest fossil of an angiosperm found is about 125 million years old
- The tallest flower is Titan arum, growing to a massive 10 feet tall and stinking of rotting flesh
- In 17th century Holland, in an event called tulip mania, tulip bulbs sold for as much as 10 times the annual salary of a skilled craftsman
- Angiosperms are the most diverse group of land plants
- Angiosperms surpassed gymnosperms as the dominant plant species about 60 million years ago

Amborella trichopoda
Bellendena montana
Canella Winterana
Tulipa saxatilis
Eurayle Ferox
Illicium floridanum
Land Plants (Embryophytes)
All land plants are terrestrial
They are all complex multicellular eukaryotes
Have specialized reproductive organs
Apical meristems
All have cuticles for water conservation
All have stomata for gas exchange
Development of the zygote into a multicelluar, dipolid sporophyte take place in the archegonium
The sporophyte generation is dominant
All have lignin
Importance to Humans
They help maintain the atmosphere by replenishing it with oxygen
They capture energy from the sun and can be used as a food source
They build up soil with their roots
Provide "pleasure"
Can be used as a source of fuel
Niches/Ecological Roles
Take in carbon dioxide and release oxygen for the use of by other organisms
Strengthen soil
Source of habibtat for some other organisms.
Are primary producers, and provide the energy that is used by the rest of the food chain
Interesting Facts
Evolved from streptophyte green algae
Almost all the energy that terrestrial organisms obtain comes from either land plants or angiosperms.
Lignin helps not only support the plant, but also expose the maximum amount of surface area to the sun.
Before the move to land, plants had no roots, cuticles, stomata, or lignin.
There are close to 15,000 known species of land plants.
Embryophytes are the most familiar sub kingdom of green plants that form vegetation.
- Rhizomatic aquatic herb
- Broad leaf base
- Basal Angiosperm

- Diverged very early on in angiosperm evolution
- Trimerous flowers
- Pollen with one pore
- Branching veined leaves

- Eudicot
- Flowers are hermaphrodite
- First to diverge from family proteaceae

- Monocot
- Herbaceous
- Perennial

Molecular phylogenetic analyses place it at the base of angiosperms
Flowers of one plant are either male or female, with a nonfunctioning stamen or carpel, respectively.
very basic angiosperm, not many other adaptations

"embryophyte." A Dictionary of Biology. 2004. "Embryophyte." Encyclopedia.com. HighBeam Research, 01 Jan. 2004. Web. 26 Mar. 2015.

"Embryophytes." Embryophytes. N.p., n.d. Web. 26 Mar. 2015.

"Annals of Botany." Streptophyte Algae and the Origin of Embryophytes. N.p., n.d. Web. 26 Mar. 2015.

"Marchantia." Bahasa Indonesia, Ensiklopedia Bebas. N.p., n.d. Web. 26 Mar. 2015.

The Biology Primer. N.p., n.d. Web.

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Botanical. N.p., n.d. Web.

"Rhyniopsida." Wikipedia. Wikimedia Foundation, n.d. Web. 27 Mar. 2015.

Alglaophyton major
- Do not have true roots : stems of leaves
- Cell walls composed of cellulose
- No vessels for transport
- Spores can look needle-like
- Have leaves in the gametophyte
- Multicellular Rhizoids
- Lack true xylem
- Contain branched sporangic
- No true vascular tissue,
- Hydroid-like conducting cells
- No roots
- No leaves
- Roots produced sporangia at their stem tips
- Vascular
"Angiosperms." Angiosperms. N.p., n.d. Web. 27 Mar. 2015.
"Bellendena." Wikipedia. Wikimedia Foundation, n.d. Web. 27 Mar. 2015.

"Canella." Wikipedia. Wikimedia Foundation, n.d. Web. 27 Mar. 2015.

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"Tulip Mania." Wikipedia. Wikimedia Foundation, n.d. Web. 27 Mar. 2015.
They all have a notocord- a rod-like elongated skeletal structure that is dorsal to the gut.
The nerve cord develops dorsally in all chordates.
All chordates have visceral clefts and arches.
Importance to Humans
Humans are members of the phylum chordata.
Many of important human food sources are chordates.
Many chordates compose secondary portions of the food chain.
By being secondary in the food chain, less complex chordates can keep humans alive.
Chordates aare used in medical studies for human vaccines
The also help keep the ecosystem alive.
Niches/ Ecological roles
- Multicellular
- No backbone
- No cell walls
- Most are made of tissue
- Most are motile
- All are heterotrophic
- Most reproduce sexually
Importance to Humans
Many chordates keep the food chain going
They act as food sources
Keep marine and terrestrial ecosystems alive through metabolic processes and fertilizing the soil for plants
- Many insects feed on organic waste to clear up land for people
- Some invertebrates help pollinate plants that are used by humans
- Invertebrates are part of the feeding cycle of many other animals to control pests that destroy farmers' crops
- Provide for medical organic materials
Interesting Facts
Niches/ Ecological Roles
- Invertabrates are a big part of the aquatic and terrestrail feeding cycle
- Pollinate the flowers of many plants
- Some, such as earthworms, decompose waste to make better soil for plant growth
Interesting Facts
- 97% of all known species are invertebrates
- Most invertebrates go through metamorphosis
- Many of the world's parasites are invertebrates
- Invertebrates were the fist animals to evolve
- Some invertebrates form large colonies
- Invertebrate exoskeletons do not grow with them
Segmented Worms
Sea Stars
- sessile as adults
- body made of pores
- filter feeders
- most are hermaphrodites but some reproduce asexually

- radially symmetrical
- no brain, blood, or nervous system
- propel themselves through water
- made of three layers
- made of three cell layers
- sexual reproduction
- large surface area to volume ratio
- bilateral symmetry
- cephalization
- most have a muscle system
- bilateral symmetry
- made of three layers
- contain a false body cavity
- normally reproduce sexually
- circulatory system
- bilateral symmetric
- soft body without skeleton
- made of hard plates
- tube feet help with movement
- can reproduce asexually
- able to regenerate limb
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"Biology of Animals & Plants - Flatworms." Biology of Animals & Plants - Flatworms. N.p., n.d. Web. 29 Mar. 2015.

"Ecological Importance and Invertebrate Conservation." Cambridge Journals Online. N.p., n.d. Web. 29 Mar. 2015.

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"Ryan Photographic - Sponges." Photos of Sponges. N.p., n.d. Web. 29 Mar. 2015.

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"10 Interesting Facts about Invertebrates - Saturday, 19th January 2013." Wildlife Village. N.p., 18 Jan. 2013. Web. 29 Mar. 2015.
There are over 58,000 known species of chordates.
All chordates posses an endoskeleton.
They can be warm or cold-blooded.
Chordata have the most complex brains out of all the other phyla.
Can be omnivores, carnivores, or herbivores.
They have a complete digestive system.
"Chordates." Chordates. N.p., n.d. Web. 29 Mar. 2015.

"Descriptions and Articles about the Chordates (Chordata) - Encyclopedia of Life." Encyclopedia of Life. N.p., n.d. Web. 29 Mar. 2015.

"Cionidae." Wikipedia. Wikimedia Foundation, n.d. Web. 29 Mar. 2015.

"Ascidiacea World Database - Diazonidae Seeliger, 1906." Ascidiacea World Database - Diazonidae Seeliger, 1906. N.p., n.d. Web. 29 Mar. 2015.

"Sea Squirts | DIAZONIDAE | Rhopalaea Species | Marine Iconography of the Philippine Archipelago | Poppe-Images." Sea Squirts | DIAZONIDAE | Rhopalaea Species | Marine Iconography of the Philippine Archipelago | Poppe-Images. N.p., n.d. Web. 29 Mar. 2015.

"Styelidae - Information on Styelidae - Encyclopedia of Life." Encyclopedia of Life. N.p., n.d. Web. 29 Mar. 2015.

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"Pyuridae - Information on Pyuridae - Encyclopedia of Life." Encyclopedia of Life. N.p., n.d. Web. 30 Mar. 2015.

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"WoRMS - World Register of Marine Species - Molgulidae Lacaze-Duthiers, 1877." WoRMS - World Register of Marine Species - Molgulidae Lacaze-Duthiers, 1877. N.p., n.d. Web. 30 Mar. 2015.

"Sea Grape, Molgula Manhattensis (Pleurogona: Molgulidae) - 5431583." Sea Grape, Molgula Manhattensis (Pleurogona: Molgulidae) - 5431583. N.p., n.d. Web. 30 Mar. 2015.

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"Tunicates - Tunicata." Tunicates - Tunicata. N.p., n.d. Web. 30 Mar. 2015.
Family of sea squirts
Body is usually about 100-150 mm in length
Have 2 syphons at their anterior ends.
Another family of sea squirts
Diazonidae are suspension feeders
Marine organisms
Suspension feeders
Stays within 0-9.7 M elevation
Family of tunicates
Live in limited geographical ranges
Their max water depth is 5.744 meters
Another family of tunicates
Live in marine environments
Suspension feeders
Type of tunicate
Live in a marine environment
Range from 1 inch to 2.4 inches
Importance to Humans
Niches/ Ecological Roles
Interesting Facts
Only member of mammalia other than platypuses that lay eggs
Covered in coarse fur and spikes
Also known as spiky ant eaters
Give live birth but child is not capable of surviving on own yet, lives in mothers pouch
Exhale as hopping, inhale as landing, makes hopping energy efficient
Two-toed Sloth
Have one of the lowest metabolic rates of all mammals
Spend most of time in trees, only leave trees to expel waste
Vampire Bats
As name implies, food source is blood.
Wonderful demonstration of convergent evolution, flying mammals developed independently of birds
All have a back bone or spine
Are endothermic, or warmblooded, allow them to regulate own body temperature without being influenced by the outside environment
Have hair in some amount on their bodies
Females produce milk in mammary glands for young to feed off of

Mammals are by far one of the most important classes of organisms to humans, after all - we are mammals! Mammals provide many of the foods we eat and the things we drink, cows and pigs being prime examples of this. We also perform many experiments on mammals when researching various medications, features, etc since they share many characteristics and we can learn more about ourselves from them.
Mammals have a very large impact on the ecosystems they are a part of. Mammals are the current dominant life form on the planet, and as such they often make up the highest layers of the food chain. It would be impossible to talk about mammals and their ecological role without mentioning humans. Humans have a profound ecological impact, whether through causing changes in the environment (pollution, destruction/creation of habitats) or through the consumption of organisms in the environment (hunting, farming, etc.)
Odds are if you're reading this, you're a human
Unique in brain size relative body, use advanced reasoning skills as main survival adaptation
Use hairs on body to detect water currents and other nearby animals
Capable of associative learning
Lack of hind limbs
There are over 4,200 species of mammals
Mammals appeared about 200 million years ago
The largest mammal is the blue whale at a massive 74 tonnes
The smallest mammal is the bumblebee bat, measuring in at a tiny 1 inch and weighing about 2 grams
The most diverse groups of mammals are rodents and bats
Hooded seals have the shortest infancy to adulthood development rate, reaching adulthood in about 4 days after birth, the fastest of all mammals
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Man and Woman in Northern Thailand. Digital image.
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Digital image. N.p., n.d. Web. 30 Mar. 2015.
Digital image. N.p., n.d. Web. 30 Mar. 2015.
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