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Home , Agnostida, Agnostus, Asaphida, Asaphidae, Aulacopleura, Balcoracania

PALEONTLOGY 5: SPECIATION

VOLUME 9, ISSUE 5, January 2020

THIS MONTH DESCENT WITH MODIFICATION • Hierarchy page 2 • page 3 • page 4 The Era lasted from • Size page 7 541 to 252 million years divided • Characteristics page 10 into six Periods: • DNA page 16 • • Speciation page 19 • • Fun Facts page 23 • • POWER WORDS • • BYA: billion years ago • • eukaryote: organism consisting of a cell or At the end of the , cells in which the there is evidence of soft-bodied, as an example of how all genetic material is in multicellular organisms (mostly organisms speciate. Trilobites chromosomes frond-like and tubular forms) are incredibly awesome! contained within a found in locations around the distinct nucleus world. This is called the The Ute Tribes are now located • phylum: (plural phyla) a Ediacaran biota. These in SW Colorado and Utah. They major division of life were composed of individual roamed throughout the Western after Kingdom and cells organized into colonies, Rocky Mountains, venturing before Class (see pg. 2 like . onto the Eastern Plains. They for more information) found Cambrian trilobites and • prokaryote: a The refers carried them as protective microscopic single- to a burst of . The reason charms, “Timpe-Konitza- celled organism with no is simple; animals developed Pachuee.” or “little water bug internal membrane hard parts, like shells. We find living in a house of stone.” bound organelles, DNA fossils representing almost all of is in a circle the 35 phyla! The only Samuel Turvey found new modern animal phylum missing Chinese trilobites. He gave one CAREER CONNECTION is Bryozoa, moss animals. of them the name of • Interview with Dr. Smith, after the biggest ethnic group in paleontologist page 24 This issue focuses on trilobites, China. The name is both their natural history but also Han solo!

COLORADO STATE UNIVERSITY EXTENSION 4-H PROGRAMS ARE AVAILABLE TO ALL WITHOUT DISCRIMINATION

HIERARCHY — Organizing Life 2

A mnemonic is a trick to help like the . POWER WORDS remember something. Here is a ○ Within Order Proetida are • Archaea: microorganisms mnemonic for planets: 13 Families, like Family similar to bacteria in size and My — Mercury . simplicity but different in Very — Venus ○ Within Family Proetidae, molecular organization Educated — Earth there are 288 Genera • chromosome: threadlike Mother — Mars including Genus . structure of DNA found in the Just — Jupiter ○ Within Genus Proetus are Served — Saturn two species, P. concinnus nucleus of eukaryote cells Us — Uranus and P. latifrons. carrying genetic information Nachos—Neptune in the form of genes Directions: • hierarchy: taxonomic Before advanced technology in • Develop a mnemonic to classification of successive molecular techniques, Dr. Carl help you remember the levels of complexity of life Woese and Dr. George Fox hierarchy of life: • mnemonic: a device such painstakingly analyzed a very as a pattern of letters, ideas, stable section of DNA of Domain— or associations that assists hundreds of organisms. They Kingdom— in remembering something found a hidden group of single- • molecular techniques: celled prokaryote organisms, Phylum— manipulation and analysis of distinct from bacteria, and called Class— DNA, RNA, and/or proteins them archaebacteria (now called Order— • organelle: organized or Archaea). Domain Eukaryota specialized structures bound organisms can be single-celled Family— by a membrane within a or multicellular. They are Genus— living cell distinct from both Domain Bacteria and Domain Archaea: Species— DNA is formed into chromosomes residing in the cell’s nucleus, and the cell contains organelles. Domain is the highest hierarchy, and all known life falls into one of these three Domains.

Within the Domain Eukaryota are 10 Kingdoms, seven of which are mostly single-celled organisms, and three contain multicellular organisms: • Kingdom Plantae (plants) • Kingdom Fungi (fungus) MATERIALS • Kingdom Animalia (animals) ○ Within Kingdom Animalia • Paper are 35 phyla, including • Pencil Phylum Arthropoda. ○ Within Phylum Arthropoda is the Class Trilobita (also known as Trilobitomorpha) ○ Within Class Trilobita are 10 Orders of trilobites,

TRILOBITES — A Paleozoic Success Story 3

The Cambrian Explosion of the fauna in POWER WORDS occurred 541 MYA and lasted the 1980s. These three men • e.g.: Latin for exempli 20 million years. During this were instrumental in bringing to gratia meaning for the time, almost all major animal light the amazing and wonderful sake of example, or for phyla appeared in the life that had lived in there half a example record. Not only that, but there billion years ago! • fauna: animals from a were some weird and wonderful particular region, experiments in life, like Opabinia The Burgess Shale is not the habitat, or geological regalis. with 5 eyes and a long only location from this time in period proboscis, and Marrella Earth’s history with well • MYA: million years ago splendens. (the lace crab—but preserved fossils. There are • proboscis: elongated not a crab), the most common three other places in the world appendage from the animal in the Burgess Shale. that remarkable preservation of head of an animal (e.g. fossils from this time: elephant trunk) The Burgess Shale is a location Chengjiang and Doushantuo, • stratum (plural strata): in British Columbia that is a both in China, and Sirius Passet layer, or series of treasure trove of these amazing in Greenland. There are fossil layers, of rock in the Cambrian fossils. It was found sites throughout the world, just ground in August 1909 by Charles not with the detail of the Doolittle Walcott, paleontologist ecosystem preserved, like it is in from the Smithsonian. It was these four site. almost at the end of the season, so the following year, Walcott The earliest known trilobites are and his family returned and from 521 MYA found in Siberia, began extracting these Morocco, Spain, and North incredibly well preserved fossils, America. At this time, the both hard and soft bodied evidence indicates that trilobites organisms, from this site dated originated in Siberia, and then 508 MYA. migrated throughout the world. They survived 250 million years. Walcott and his family continued During this time, they speciated collecting at this site until 1924, into over 20,000 species! and had collected over 65,000 specimens for the Smithsonian. Directions: They were considered only a • Explore the links in the green curiosity, and were not studied box below, A Guide to the again until 1962, when Alberto Orders of Trilobites and Order , sp. Simonetta recognized that many American Museum of Natural may represent the ancestral of these fossils did not fit in History Trilobite Website. trilobite. modern groups. MATERIALS The quarry was reopened by the • Computer with internet Geological Survey of Canada • https://www.trilobites.info/ under a trilobite expert Harry • https://www.amnh.org/researcHpaleontology/ Blackmore Whittington. Dr. collections/fossil-invertebrate-collection/trilobite- Whittington had two graduate website students, Derek Briggs (now • Optional: Gould, Stephen Jay (1989) Wonderful with Yale University) and Simon Life: The Burgess Shale and the Natural Conway Morris (now with History, W.W. Norton & Co. Your county library University of Cambridge), who has a copy, or can find one for you. Wonderful began a thorough assessment story! A must read!

TRILOBITES — Eyes 4

Prior to the Cambrian, there is In this activity, you will make an POWER WORDS no fossil record of organisms model of a single facet of a • accommodate: the with eyes. Cambrian fossils, trilobite eye. ability of the eye to however, show many different change focus from forms of eyes. Eyes can be Directions: distant to near objects simple light sensing cells • Do this by a window during • analogous: structures differentiating between shade the day. performing similar and full sun or extremely • Stand on one side. Hold function but having a complex, like human and bee your paper vertically in the different origin; eyes. Of the 10 Orders of hand farthest from the example insect wings Trilobites, nine Orders had window. and bat wings compound eyes, similar to • Hold the • biconvex: surface insect eyes. Trilobites came up biconvex lens curved like the exterior with a unique solution for a lens vertically in the of a circle on both sides —they used calcite. other hand. Be • birefringent: light will sure that the travel in two different Calcite is a mineral composed of light from the directions when calcium, oxygen, and carbon window through passing through a (CaCO3). It is found throughout the lens to the material like calcite the world. Some forms of calcite paper is not • circumference: the have a unique property: they are blocked. distance around clear and birefringent (cool • Move the lens slowly back something science word!) See the image and forth until the image • compound eye: an eye below how light splits. comes into sharp focus on consisting of an array of • bi means two the paper. Measure and numerous small visual • refringent means split record the distance between units, as found in the paper and the lens. This crustaceans or insects is called the focal length. Definitions continue page 5 Different lenses have different focal lengths. If you have more than one lens, do the same with each lens. Record each measurement. • TP tubes are 4” long, and paper towel tube is 11” long. If your focal length is longer than 7”, you need to also use the paper towel tube. Order trilobites lost their eyes. Only the very MATERIALS earliest agnostids had eyes. • magnifying lens (hand lens or biconvex lens) Agnostic means someone who • 2 TP (toilet paper) tubes and 1 paper towel tube believes that nothing can be • wax paper known about the existence or • scissors nature of God; they neither have • 1 rubber band faith nor disbelief in God. In • tape other words, the agnostid • ruler and pencil trilobites do not see the light, a • optional: bag of lenses (search internet for a good deal— reference to this Order having around $20) no eyes! • optional: clear calcite (ask at a rock shop—around $8)

TRILOBITES — Eyes 5

• Your tubes will be like a towel tube down the POWER WORDS (cont.) telescope. One tube nests length, and tape it • diameter: a straight inside the other tube. Cut together with a slightly line passing from side one TP tube down the smaller diameter so it will to side through the length, and tape it together fit inside the wider TP center of a body or with a slightly smaller tube. Cut the paper towel figure, especially a diameter so it will fit inside tube ½” shorter than the circle or sphere the other TP tube. If your lens with the longest • facet: any of the lens with the longest focal focal length. individual units length is over 8”, you need to  Example: The focal (ommatidia) that make use a paper towel tube. length is 8”. Cut the up the compound eye • If you have different lens paper towel tube • focal length: the focal lengths, you can lengthwise, and tape it distance from the lens adjust your tubes to back together with a to the image in focus accommodate for each focal smaller diameter to fit • homologous: similar in length. This is similar to our inside the TP tube. position, structure, and ability to keep close objects Also cut the paper origin, but not in or far objects in focus. towel tube shorter, so function; example bird ○ Use the distance of the that it is 7½” long. and bat wings lens with the shortest • Attach a small piece of wax focal length. If your paper to the shorter outer TP Definitions start page 4 focal distance is less than tube and fasten it with a 4”, cut your inner, thinner rubber band. If the wax tube’ circumference ½” paper is wrinkled or ripped, it shorter than your focal will be easy to replace. length. Cut your outer, • Insert the longer tube into the fatter tube 1” shorter than shorter tube. Telescope the the focal distance. tubes as long as possible.  Example: The focal • Stand in front of a window. length is 3.5”. Cut Hold the magnifying lens in the outer, wider tube one hand. Hold the tubes in 1½” around the the other hand, with the wax circumference so the paper towards you. Hold the tube is 2½” long. Cut lens and tubes arms-length the longer, inner tube away. 1” so it is 3” long. • Slowly push the lens against ○ If your focal length is 4½ the furthest tube, decreasing to 7”, only cut your outer, the length of the tube. Look The longer thinner tube nests fatter tube ½” shorter. at the wax paper. The image inside the shorter, wider tube  Example: The focal will come into sharp focus. with wax paper on one end. length is 4½”. Cut only the outer, wider TRILOBITE EYES— tube by ½” so that it is 3½” long. The thinner tube remains 4” long. ○ If your longest focal length is over 7”, you will need to use a paper towel tube in addition to the TP outer tube. Cut the paper

TRILOBITES — Eyes 6

Reflect : POWER WORDS • Describe the image. What do • invert: put upside down you notice about it? • receptor: an organ or • Wax paper represents the light cell able to respond to sensitive cells that send the light, heat, or other image to the brain. The lens external stimulus and represents the calcite lens. transmit a signal to a • Your “eye” represents only a sensory nerve single facet. Trilobite fossils a. • secondarily lost: had many facets, some had organisms whose 15,000 facets per eye! ancestors had a • What is the advantage of so structure that is no many facets? They are longer present (e.g. extremely motion sensitive. mice and squirrels have • A calcite lens is hard, and secondarily lost their cannot accommodate. thumbs and only have Instead, they relied on the four fingers; their birefringent properties of ancestors had 5 calcite to change focus. fingers) • There are three “styles” of b.

trilobite eye:

a. Holochroal eye is the most

common. It has a few to Image below is the best over 15,000 facets; no separation between facets. understanding bee scientists b. Schizochroal eye; fewer, think bees see through their larger facets separated by a compound eyes. sclera (like the whites of our eyes). Found in few species in Order . c. Abathochroal eye: flat facets found only in a few c. primitive agnostids from the Early Cambrian. d. Trilobites that lacked eyes are thought to have secondarily lost them. Organisms living in caves or deep in the ocean secondarily lost eyes. d. • How a basic eye works: ○ Light passes through an opening

usually with a lens to focus the light. ○ The image is inverted. ○ Light receptors are located focal distance (or so) behind the lens. ○ Receptors send electrical signals to the brain for interpreting the light. If the eye does more than sense light and dark, the brain re-inverts the image.

TRILOBITES — Sizes 7

Trilobite size ranges from tiny to Trilobites had three body parts, POWER WORDS huge (well, huge for a trilobite), similar to insects. They had a • cephalon: in trilobites • The smallest trilobite found is cephalon (head), thorax (chest) and some other Acanthopleurella stipulae in and (tail). , the region the Order . It is of the head, composed only 1-2 mm (size of a fleck of fused segments of pepper). • pygidium: the hind • The largest known trilobite is segment of the body in rex in the Order certain invertebrates . It is 28” long and • segments: (also called 18” wide. It lived during the ribs) each of the series Ordovician, and the fossil of similar anatomical was found in Manitoba, units of which the body Canada. and appendages of some animals are Trilobites had a broad spectrum composed, i.e. rings of of feeding habits, ranging from an earthworm's body predatory to filter-feeders. That • thorax: the middle mean to their mouth parts were section of the body of different. See https:// an insect or trilobite, www.trilobites.info/feeding.htm between the head and for a discussion on feeding and The name trilobites means three the abdomen, bearing mouth parts. An example of a lobes. This does NOT refer to the legs filter feeder Cordania is pictured their three body parts, but to the below. left, center and right sections that ran down their bodies as shown by the yellow arrows on Postikaolishania jingxiensis, the trilobite imaged on the right.

Different species have a different number of repeating segments along their thorax and pygidium. The white arrow shows one of the 16 segments on Postikaolishania jingxiensis. Some trilobites had amazing structures, like Walliserops Many trilobites have spines. trifurcatus pictured below. The blue arrow points to a plural Scientists are not sure how the spine. “trident” was used, but it could have been for protection or mating rituals. MATERIALS • stove • 3 cup flour • large pot • 3 cup water • wood spoon • 6 tsp cream of tarter • measuring spoons • 1 cup salt • measuring cup • 3 TBS vegetable oil • adult supervision • red food color • wax paper • green food color • computer & internet cont. on page 8

TRILOBITES — Sizes 8

Finally, if you turned a trilobite place the dough in a gallon POWER WORDS over, beneath the carapace baggie to cool 30 minutes. • carapace: the hard were legs. Nested between the • When cool, knead playdough upper shell of a turtle, legs and the carapace were the in the baggie until smooth. crustacean, arachnid, gills. The drawing below is the • Store any unused playdough armadillo, or trilobite ventral (belly) side of a trilobite. in the zip lock baggie. • Tbl: abbreviation for tablespoon Sculpt your trilobites: • tsp: abbreviation for • On page 9 are three trilobite teaspoon images and information • ventral: of, on, or about them. They represent relating to the the largest trilobite, a small underside of an animal (but not the smallest) or plant; abdominal trilobite, a trilobite that is a very common size. • Using your homemade playdough, sculpt each trilobite on a sheet of wax paper. When you have completed that trilobite, place it, with the wax paper, on a cookie sheet. • When you have sculpted all For this activity, you will make three of your trilobites, playdough and sculpt 3 trilobites preheat the oven to 200°F. of different sizes. The recipe • Place the cookie sheet in the includes directions to add a oven for 15 minutes. At the brown color to your playdough. end of 15 minutes, turn off You can skip adding the color the oven, but do not open the outside. To apply, move for white trilobites. You could door. Allow the oven to the spray can in slow even add a rainbow of colors if return to room temperature broad sweeps while you want to make them colorful! with the sculptured trilobites spraying. Allow to inside overnight. thoroughly dry. Directions: • Remove the cookie tray from • Turn over the trilobite and • Measure 3 cups water and the oven. You may need to repeat on the underside pour into your pot. Add 10 let the trilobites cure longer if Allow to thoroughly dry. drops of red and 10 drops of they are soft anywhere. • You can always make green food color. Mix. If it • When completely hard, you more trilobites. Just isn’t dark enough, and can optionally apply a thin search the web for another 10 drops of red and coat of varnish to each information and images of 10 drops of green food color. trilobite. Be sure you do this them. • Add to your pot of water, 3 MATERIALS cups flour, 6 tsp cream of tarter, 1 cup salt, 3 Tbl • zip-lock bag(s) kneading and extra playdough vegetable oil and mix with • sculpting tools (e.g. wood craft stick, toothpick, the wooden spoon. nail, etc.) • Cook over low/medium heat. • cookie sheet Continue stirring until the • ruler mixture thickens and forms a • oven ball of dough. • optional spray can of varnish • Remove from the heat and

SUBTITLE — 9

Domain Eukaryota Kingdom Animalia Phylum Arthropoda Class Trilobita Order Asaphida Family Genus Isotelus Isotelus maximus (to the right) Upper Ordovician Found North America • 15” long • 8” wide • Center lobe higher than the left or right lobes • genal spines (deriving from the cephalon) • 8 segments (ribs) in the thorax

Domain Eukaryota Kingdom Animalia Phylum Arthropoda Class Trilobita Order Odontopleurida Family Genus Dicranurus monstrosus Upper Devonian Found in Morocco • 2.25” long • 1” wide, with genal spines, 2.5” • Center lobe higher • genal and plural spines • 2 curling occipital spines (like ram horns) • 10 segments (ribs) in the thorax

Domain Eukaryota Kingdom Animalia Phylum Arthropoda Class Trilobita Order Agnostida Family Peronopsidae Genus Itagnostus Itagnostus interstrictus Middle Cambrian Found Asia, Australia, Europe, and North America • 1/2” long • 1/4” wide • 2 segments (ribs) in the thorax • no eyes • cephalon and pygidium similar

TRILOBITES — Characteristics 10

The past two ST[EMpower] any information included POWER WORDS newsletters explored (when in time it lived). • characteristic: a feature or cladograms. Both shared and • It will be easier if you print 4 quality belonging typically to derived characteristics Order Characteristics pages a person, place, or thing and determine how the cladogram 11—12, but it is not serving to identify it is made. necessary. You can print • cladogram: branching that double sided or single diagram to show In this activity, you will identify sided. relationships specific characteristics on 24 • Print page 13, the table on species of trilobites from 4 the trilobite characteristics. • derived characteristic: a Orders. For example, orders of • The trilobite body has three characteristic that trilobites have different number major body parts. The originates in a lineage (or a range of numbers) of cephalon, or head (colored • glabella: smooth part of the thoracic segments. in pink in the image below forehead between and left), includes mouthparts above the eyebrows; similar The "fossils" are paper and sensory organs such as places on non- representations of real trilobites. antennae and eyes. The • lineage: lineal descent from We are only looking at four thorax (colored yellow) has an ancestor Orders of Trilobites; scientists, multiple similar segments • lineal: in a direct line of however, have placed all (that allowed some species descent trilobites into 10 different Orders. to roll into a defensive ball. • originate: having a specified Trilobites were extraordinarily The pygidium, or tail section beginning successful animals, and (colored green), is the third • shared characteristic: a scientists have found over body part. Color the three characteristic that is in body parts (pink cephalon, 20,000 different species! common with two lineages yellow thorax, and green Eyes • thoracic: of the thorax pygidium) on each of your 24 trilobites with the color pencils. ○ Identify if cephalon Glabella • Use the table on page 13 to genal spines are present. Genal record the following answers ○ spine on your trilobite: Identify if the pygidium ○ Count and record the is spiny or spineless. number of segments on ○ Is your trilobite tiny? 14 the thorax. ○ Is the glabella large segments ○ Identify if that trilobite has or small? eyes. Most trilobites did • Determine what Order have eyes, but not all of each trilobite belongs them did. Record that based on characteristics, with your fossil. and record that.

MATERIALS Directions: • Print the trilobite “fossils on • print pages 11—13 double sided (optional) page 14 and 15 single-sided. • print pages 14—15 single sided Each fossil is in its own • color pencils separate box, and identified • pencil or pen by genus name. • • Cut out each fossil along the box border so you keep the picture trilobite together with

TRILOBITES — Characteristics 11

Trilobite Orders Characteristics

ORDER AGNOSTIDA Introduction: Tiny trilobites (usually only a few mm long) with cephalon (head) and pygidium (tail) almost the same size and shape. Cephalon: most species are eyeless Thorax: 2-3 segments (ribs). Pygidium: strongly matching the shape and size of the cephalon. Occurrence: Lower Cambrian to Upper Ordovician.

ORDER Introduction: typically spiny with bumpy . Cephalon: center part of head (called glabella) is broad and large; eyes usually present. Thorax: between 8-13 segments (ribs), usually spine-tipped Pygidium: often longer than wide, typically ending in spiny tips. Occurrence: Middle Cambrian to Upper Devonian

TRILOBITES — Characteristics 12

Trilobite Orders Characteristics

ORDER PROETIDA three lobes distinct Introduction: typically small trilobites, on head sometimes with pits or small bumps. One species of this order was the last group of trilobites to exist before the species went extinct. Cephalon: each lobe distinct on the cephalon; glabella large; eyes usually present and large, typically with genal spines Thorax: 8–22 (typically 10) segments (ribs), tips variable, blunt to long-spine. Pygidium: often spineless, with 4-10 furrows Occurrence: Lower Ordovician to Upper Permian

usually spineless and 4-10 furrows

ORDER REDLICHIIDA Introduction: Numerous thoracic segments (ribs) with spinose tips. One of the earliest species of trilobites. Cephalon: large and semicircular; genal spines strong; eyes typically large, crescentic with ridge Thorax: with numerous segments (up to 60+ ribs), and spiny tips Pygidium: typically tiny with one or very few segments. Occurrence: Cambrian

TRILOBITES — Characteristics 13

Genus of Number of Eyes Genal Pygidium Size Tiny Glabella Order Trilobite Segments Present? Spines Spines Large Acidiphorus

Agnostus

Arctinurus

Aulacopleura

Balcoracania

Bathyurus

Condylopyge

Cornuproetus

Cyphaspis

Cyphoproetus

Damesella

Dicranopeltis

Fallotaspis

Kettneraspis

Olenelloides

Olenellus

Paedeumias

Pagetia

Paradoxides

Phaetonellus

Phillipsia

Platyantyx

Redlichia

Selenopeltis

TRILOBITES — Characteristics 14

Acidiphorus Mid Ordovician Mid Cambrian Lower Silurian

Agnostus Bathyurus Cyphoproetus Mid Ordovician Lower Ordovician Permian

Arctinurus Damesella Mid Ordovician Lower Ordovician Lower Silurian

Aulacopleura Cornuproetus Dicranopeltis Upper Silurian Mid Devonian Upper Cambrian

TRILOBITES — Characteristics 15

Fallotaspis Paedeumias

Lower Cambrian Mid Cambrian Upper Carboniferous

Kettneraspis Platyantyx Upper Silurian Upper Cambrian Lower Silurian

Olenelloides Paradoxides Mid Cambrian Mid Cambrian Lower Cambrian

Olenellus Phaetonellus Mid Cambrian Upper Ordovician Upper Silurian

DNA — Dominant and Recessive Alleles 16

Species have the ability to adapt study, solitude, and prayer. He POWER WORDS to changes in their environment experimented with peas to figure • allele: one of two or over generations. That is out how genes work. more alternative forms because populations carry a of a gene, for example hidden reserve in its DNA in the Genes are instructions how to curly or straight hair in recessive gene pool. make an organism. You inherit Caucasians genes from your mother and • chromosomes: thread- genes from your father. That like structures of means you have two versions of nucleic acids adenine all your genes. The different (A), thymine (T), versions of the same gene are guanine (G), and called alleles. The gene cytosine (C) see https:// function remains the same. For tra.extension.colostate.edu/ example, we have three alleles stem-k12/stem-resources/ for our red blood cells: A, B, and 3, page O. These three alleles give us 18 for more information our blood of A, B, AB, or O. • expression: the allele The only way to inherit O blood that is translated into a is if both parents have O blood. function Genes Blood Type • gene: a unit of heredity Mom/Dad which is transferred DNA in eukaryote cells (our A/A from a parent to cells are eukaryote) come in A A is dominant offspring and is held to pairs of chromosomes. One is determine some from our mother, and the other A/O A is dominant A (O is hidden) characteristic of the is from our father. Different offspring species have different number of O is recessive chromosomes. For example, A/B AB body, and carbon dioxide humans have 23 pairs of A & B are codominant from our body to be expelled chromosomes, and the two- B/O by our lungs. The function is toed tree sloth Choloepus B is dominant B (O is hidden) the same. didactylus (means lame-foot two O is recessive

-toes) has a varying number of B/B B 26-32 pairs of chromosomes, B is dominant plus a couple of unmatched! O/O O Weird mammals for sure! O is recessive Regardless of our blood type, the red blood cells still carry oxygen from our lungs to our

MATERIALS • coin • large marshmallows • 2 flavors of frosting (i.e. chocolate and lemon) Gregor Mendel, the Father of • red, yellow, green, blue decorating sparkle gels Genetics, lived in the 1800s in • pretzel sticks what is now the Czech Republic. • mini-marshmallows in 4 colors He was a monk, a member of • plate the Catholic Church devoted to • butter or plastic knife • print page 18—three copies (opt. double-sided)

DNA — Dominant and Recessive Alleles 17

Genes followed certain patterns: you have three body parts, POWER WORDS • dominant or recessive attach the third marshmallow • genotype: the genetic (dominant allele is with another pretzel stick. make-up of an expressed and recessive • Our monsters have 6 limbs individual allele is hidden, like AO (legs, arms, antennae, etc.). • phenotype: observable blood type, only A is Add your monster 6 limbs. characteristics of an expressed, and O is hidden) • The color of the body is individual based on • codominant (both alleles are controlled by a gene with 2 genotype expression expressed, like people with alleles: dominant is blood type AB inherited A chocolate and recessive is Genetics Punnett Square from one parent and B from lemon frosting. Flip your • Mom: tri-colored the other parent) coin and record (H or t). beagle, but carries the • incomplete dominance • The color of the appendages lemon allele (T/H) (alleles blend together, like (all 6 of them) are either blue • Dad: lemon beagle (H/H) curly hair and straight hair (H dominant), yellow (t • What are the chances parents will have a child with recessive) or a combination of a lemon puppy? wavy hair) of the two (green) if both H (Two out of 4 puppies • multiple genes influence the and t (incomplete will be lemon.)

trait (like the 378 genes that dominance). Mom (H / t) modify skin color in humans!) • The number of the eyes: 5 H t small if H dominant or 3 large

In this activity, you will make t recessive. H / t t / t t three monster offspring based • Eye color is red (H dominant) tri-color lemon on the rules of genetics. or blue (t recessive). • The mouth is either a H Dad(t/t) t H / t t / t Directions: dominant green stinger (coat tri-color lemon • We inherit traits from our a pretzel stick with green gel parents randomly. To and place in the mouth area) simulate the randomness, flip or t recessive blue open sticks—green if H a coin for each parent. (place a blob of blue gel in dominant or t yellow if Heads (H) represents the the mouth area). recessive. dominant allele. Tails (t) • Spots are H dominant yellow • Circle the number of represents the recessive or t recessive blue (make at recessive (t/t) traits on allele. If the gene is least 12 spots on the body). your data sheet. How codominant or incomplete • The nose is a mini- many are there? Circle dominance, the directions marshmallow. Add a pink the number of H/H or H/t will state what to do. mini if H dominant or orange traits? You should have • Make three monster mini if t recessive. about 1/4 recessive traits offspring. Complete the data • The hands and feet are mini- expressed. sheets (one for each marshmallows. Push them • Compare / contrast your monster). After you have on the ends of the pretzel three monsters. determined the genotype of • Molly is a tricolor beagle your monsters, interpret the (dominant—black in coat). phenotype. Build your three • Sam is a lemon beagle monsters based on the (recessive—no black). phenotype. If you have 2 or • Molly and Sam are from a litter of 3 body parts, push a pretzel seven puppies. Only two of the stick halfway into one puppies are lemon beagles. marshmallow, then push the • Punnett Square (above) helps us second marshmallow on the to determine the chances of a open end of the pretzel. If lemon puppy.

Assume parents carry one dominant and DNA — Dominant and Recessive Alleles 18 one recessive allele for each trait. Genotype (DNA Gene) Mom Dad Phenotype Dominant/Recessive Heads = Dominant (D) Heads = Dominant (D) (How It Looks) Codominance Tails = Recessive (R) Tails = Recessive (R) Incomplete Body Parts Heads or Tails? Heads or Tails? How many body parts? Heads/Heads—2 body parts Tails/Tails—1 body part Heads/Tails—3 body parts If 2 or more body parts, attach CODOMINANT with pretzel sticks Body Color Heads or Tails? Heads or Tails? What color is the body? Heads/Heads—chocolate Tails/Tails—lemon Heads/Tails—chocolate Use your knife to add frosting to DOMINANT/RECESSIVE your marshmallows Appendages Color Heads or Tails? Heads or Tails? What color are you Heads/Heads—blue gel appendages? Tails/Tails—yellow gel Heads/Tails—green gel Use your knife to add gel to the INCOMPLETE DOMINANCE pretzel sticks Number of Eyes Heads or Tails? Heads or Tails? How many eyes does your Heads/Heads—5 small eyes monster have? Tails/Tails—3 big eyes Heads/Tails—5 small eyes Before adding your eyes, flip DOMINANT/RECESSIVE your coin to determine color Color of Eyes Heads or Tails? Heads or Tails? What color are your monster’s Heads/Heads—red gel eyes? Tails/Tails—blue gel Heads/Tails—red gel Add eyes with your sparkling DOMINANT/RECESSIVE decorating gel Mouth Heads or Tails? Heads or Tails? What kind of mouth does your Heads/Heads—green stinger monster have? Tails/Tails—blue open Heads/Tails—green stinger Pretzel coated green gel or blob DOMINANT/RECESSIVE with blue gel Body Spots Heads or Tails? Heads or Tails? What color spots (at least 12) Heads/Heads—yellow gel does your monster have? Tails/Tails—blue gel Heads/Tails—yellow gel Dot your monster body with the DOMINANT/RECESSIVE sparkling decorating gel Nose Heads or Tails? Heads or Tails? What color nose does your Heads/Heads—pink mini monster have? Tails/Tails—orange mini Heads/Tails—pink mini Add mini-marshmallow to your DOMINANT/RECESSIVE monster’s head Feet/Hands Heads or Tails? Heads or Tails? What color hands/feet does Heads/Heads— green mini your monster have? Tails/Tails—yellow mini Heads/Tails—green mini Push the mini-marshmallow on DOMINANT/RECESSIVE the end of the pretzel sticks

SPECIATION — Tutorial 19

Different alleles may give an strictest biological sense, it is a POWER WORDS organism an advantage over group of animals that can breed • allopatric: separate others that don’t inherit the and produce fertile offspring. non-overlapping allele. There is a great example Of course it isn’t that simple, but geographical areas of this with the peppered moth it is a good place to start • fertile: able to have (Biston betularia) in England. thinking about what a species is. young or produce seed • habitat: environment of This common moth has two very Speciation happens to a group, an organism different color morphs: white- not to an individual. It generally • microclimate: climate bodied and black-bodied. takes millions, even tens or of a very small area, Before the Industrial Revolution, hundreds of million years. especially when this the black-bodied morph was Allopatric speciation can occur differs from the climate unknown. In Manchester, when a single species is divided of the surrounding area England during the Industrial by a barrier, like a new river • morph: an individual of Revolution, coal soot filled the channel cuts through a territory. one particular form in a air, covering everything with a Each side of the river could have species that has two or dark film, including tree bark. By different microclimates (see more forms the end of that century, 98% of 47.Here Comes the Sun for • offspring: children all peppered moths were dark- activities on these concepts— • speciation: formation bodied. When soot pollution https://tra.extension.colostate. of new and distinct was reduced, the white-bodied edu/stem-k12/stem-resources/ ). species in time morphs once again were The Columbia River Gorge • species: a group of favored. divides Washington from organisms capable of Oregon. The Washington south- exchanging genes or This is the most cited example facing side of the river is slightly interbreeding of natural selection. Moths with drier and warmer than the north- white-bodies were nicely facing side in Oregon, which is cooler and moister. camouflaged on the tree bark. be stronger and have more

When the bark was soot babies. The Oregon mice, What happened to a species of colored, these white-bodied on the other hand, would do mice when suddenly the moths were easily seen, and better with alleles that favor Columbia River formed through picked off by the birds. The wetter conditions. Eventually their habitat? Each side of the black-bodied peppered moths the population begins to shift river has different microclimate were camouflaged. The towards those favorable conditions. The Washington advantage favored the black- alleles. boded forms. Once pollution mice with alleles favorable to dry was reduced and the tree bark have an advantage. They can • Add millions of years… was no longer soot-stained, the • A few mutations… white-bodied moths were camouflaged, and black-bodied Note: next month’s issue will peppered moths were seen and cover mutations. eaten by the birds. Peppered Moth Through this example, we can White-bodied morph see change happen over a very short period of time. Over millions of years, this one species of moth with two distinct Black-bodied morphs could eventually become two different species. morph

What is a species? In the

TRILOBITE — Speciation 20

Reduced Segment Elongate Form POWER WORDS Thoracocare Crotalocephalina • Permo- Boundary: another name for the mass event at the end of the Permian, Ancestral Form also known as The Redlichia Great Dying • Phanerozoic: relating to or denoting the eon covering the whole of time since the beginning of the Cambrian period, and comprising the Paleozoic, Mesozoic, and Cenozoic eras Increased Segments Transverse Form Balcoracania Harpillaenus

only two Families remained extinct, they were extremely when they entirely went successful throughout the extinct at the Permo- entire Paleozoic Era. Trilobites are in the Phylum Triassic Boundary (The Arthropoda (together with Great Dying). In this activity, you will look insects, spiders, centipedes, at how trilobites changed millipedes, crustaceans, and These remarkable animals through time using the 24 some lesser-known animals), diversified into 5000 genera, images of trilobites that you Class Trilobita. They are the and over 20,000 described organized into four Orders only extinct Class of Arthropods. species. Trilobites survived (pages 10-15). You will also for about 300 million years. add when in time they were Trilobites are first found in 542 Even through they are found. Each image includes million year old rocks of the lower Cambrian. They are well preserved because they had MATERIALS calcified exoskeletons. They • Your timeline (see https://tra.extension.colostate.edu/ increased in numbers of species stem-k12/stem-resources/ 53.Paleontology 1; pg. 16) through the Ordovician (488-444 • 24 trilobite “fossils” (pages 14-15) MYA) to 46 Families. The • glue stick number of Families suddenly • 4 sharpies (e.g. black, blue, green, and red) dropped at the end of the • ruler Ordovician, and in the Silurian, • print page 22 only 13 Families remained. By • pencil the Permian (299-251 MYA)

TRILOBITES — Speciation 21 the Period (example, “Upper same Order, draw a POWER WORDS Silurian” for the trilobite horizontal line under the • designate: appoint to a Kettneraspis), and with that group (see the example to specified position. information you can place each the right with the blue arrow). • horizontal: parallel to trilobite in time on your timeline. Examine the characteristics the plane of the of the fossil above (if there is horizon; at right angles Directions: one), and determine which to the vertical • Go through your 24 individual in the group most • vertical: in a direction, “fossils” (paper trilobites) and closely resembles the one or having an alignment, sort them into the four above. Your line will such that the top is Orders: Agnostida, Lichida, connect those two trilobites. directly above the Proetida, and Redlichiida. The example indicates the bottom 1. Start with the Agnostida third trilobite (circled in red) trilobite fossils, and place is most similar to the trilobite EXAMPLE: Below is your them on your timeline in a above it. timeline with “fossils” of the vertical line. Place the • Only connect fossils in the Order (another Order trilobites in the correct same Order. of trilobites). period on your time chart. ○ Start with the Agnostida ○ Upper Cambrian “fossil” is at Do not glue your fossil to fossils. Use the ruler, the top of the Cambrian Period the time chart yet. You and draw a straight line to will want to move them the Agnostida trilobite (goldenrod arrow). around. above it. From that ○ Lower Ordovician “fossil” is at 2. Each Period can be trilobite, draw a straight the bottom of Ordovician divided by an Upper, Mid, line to the last Agnostida Period (orange arrow). and Lower designation. trilobite about it. (There You place your paper were only 3 Agnosida “fossil” at the top for trilobites.) Upper, the middle for Mid ○ Repeat for Order Lichida the bottom for Lower of but with a different color the designated Period. sharpie. Connect the 3. If you have two or more Lichida trilobites. trilobites in the same ○ Repeat with a different Order from the same time color sharpie for Order Period (e.g. two from the Proetida. Connect the Mid Ordovician), place Proetida trilobites. them side by side. ○ Repeat with a different • Repeat steps 1, 2, and 3 for color sharpie for Order the “fossils” from the Order Redlichiida. Connect the Lichida. They should be in a Redlichiida trilobites. new vertical line. • Glue down your trilobites! • Repeat steps 1, 2, and 3 for the “fossils” from the Order Proetida. They should be in ○ Three “fossils” listed as a new vertical line. Ordovician placed in the • Repeat steps 1, 2, and 3 for center of Ordovician (blue the “fossils” from the Order arrow). Redlichiida. They should be ○ No Silurian “fossils” in a new vertical line. ○ “Fossil” from the Devonian in • For the next steps, if you middle of Devonian (orange have two or more trilobite arrow). fossils side by side in the ○ Black line connects “fossils.”

TRILOBITES — Speciation 22

Natural History Museums are fossils differentiated into two POWER WORDS incredible places. The or more species (the • articulation: a point specimens they preserve are horizontal line to group connected between two kept in safety for all of us. They trilobites)? Note that on your bones at a joint that house collections of extant and timeline. allows motion extinct species for scientists to • While working in a museum, study, as well as cultural and you find the two unidentified geological specimens. For trilobites (below). Develop a example, I spent time at the list of their characteristics. American Museum of Natural Can you determine the History is in New York City Orders? collecting data on ground sloths, • Trilobite 1 Characteristics: , and their kin. The images to the right are from this museum. It shows how fossils are preserved for scientists. The fossil in the middle image is a jaw. The bottom image is a species of glyptodont.

The preparators remove rock matrix from fossils brought in from the field, preserving even ○ Order: scarring on the bones where • Trilobite 2 Characteristics: tendons attached.

After the fossils have been prepared, they are either stored in “cans” (the cabinets), or they can be articulated and displayed for the public. The third image is an articulated glyptodont Panochthus frenzelianus. Colorado has some amazing natural history ○ Order: museums. Examples: the • Where would you place them Denver Museum of Nature and on your timeline? Why? Science, or the Dinosaur Journey Museum, Museums of the West in Fruita. Trilobite 1 Trilobite 2

Directions: • Examine page 19 Trilobite Trends. Do you see any trends in the 4 Orders you examined? For example, did any of the Orders increase segments? Did any become broader? Note that on your timeline. • Was there a time when the

TRILOBITES — Fun Facts 23

• Fun Facts: POWER WORDS • Order is almost a • longitudinal: running trilobite, but it is not included lengthwise rather than here. It shares many across characteristics with trilobites, • phylogenetic: relating but also lacks one important to the development and feature: it does not have a diversification of a hard shell. Image on the species or group of right. organisms through • Trilobites thrived during the time, or of a particular Paleozoic Era. Scientists feature of an organism have found over 20,000 • scientific different species! nomenclature: the • Trilobites are arthropods. system of naming They are the only organisms; species to class that is extinct. Other depicted in either a which the organism arthropods include insects, cladogram or an belongs is indicated by arachnids (spiders and phylogenetic tree. two words, the genus scorpions), crustaceans • Scientific nomenclature is and species names, (shrimp and crabs), like your first and last name, which are commonly millipedes and centipedes. but the last name always Latinized • The name trilobite refers to goes first. The genus and the three longitudinal lines species names are in italics along its body, not the three when typed, or underlined if body parts. Trilobite means: handwritten. Genus is ○ tri – three capitalized, but species ○ lob – lobes name is not. Example: ○ ite – rock Tyrannosaurus rex • A lobe is the roundish and ○ If the genus name is unknown but you flattish part of something understood, you can use know the genus • The suffix “ite” means formed the initial instead. name, you can use from rock or stone Example: T. rex. “sp.” as in • Trilobites were one of the ○ If the species name is Tyrannosaurus sp. first species to have eyes! • The largest trilobite ever found is Isotelus rex, over 28 inches long! The image to the right shows some of the largest trilobites found so far. • The smallest trilobite, Agnostida, is a bit smaller than 1 millimeter. It is about the size of a grain of rice! It did not have eyes. • The age and morphology (shapes and forms) of fossils can be used to place them in sequences. This reveals the patterns of changes that have occurred over time. This relationship can be

CAREER CONNECTION — Interview with Dr. Smith 24

When most people think of a • university professor POWER WORDS paleontologist, they think of • fossil preparator • Cenozoic: current Era, someone digging up dinosaur • community college professor starting with the end of fossils. While some • educator (university, nature dinosaurs and paleontologists do just that, center, museum, etc. continuing to today most other paleontologists study • ecological: relating to different times, places, or All positions require at least an or concerned with the species. undergraduate degree in biology relation of living and geology, and for museums organisms to one Dr. Smith studies Cenozoic Era and universities, you would need another and to their fresh water fish. There are more a Ph.D. physical surroundings kinds of fishes in the world than • morphological: all other vertebrate animals Job satisfaction is extremely relating to the form or combined. About half of the high for paleontologists. We just structure of things 25,000 species live in love the “work.” Pay is decent to freshwater, even though this support a family, but you habitat is less than 1% of the probably won’t become a total water on the planet. The millionaire. nature of species restriction to river and lake drainages has What is job satisfaction? It is a contributed to their reproductive feeling of fulfillment and isolation and species origins. enjoyment that a person derives from their job. You could make Cenozoic fish paleontology a million dollars, hate what you reveals ecological causes of do, and what do you have? You morphological change through only have a million dollars. You time, past drainage isolation and could make a descent living and connections, causes of love what you do and what do extinction, and a surprising you have? A great life! meaningful to me?” That amount of hybridization that depends on your interests, reunites lineages and changes In each ST[EMpower] issue, talents, and life-style the rates of organism’s change there is a Career Connection. It choices. The goal of these through time and speciation. is to help you find jobs that you Career Connections is to will love to do. For Dr. Smith, help you find a career that Dr. Smith is a member of the paleontology is the job that gives gives you meaning. “Ask a Paleontologist” Team for him satisfaction and meaning. the Society of Vertebrate Paleontology http:// While you continue working on vertpaleo.org/. If you have a your career journal, keep asking question about a fossil, he is yourself, “Will this work be one of the people who will respond to your question. Dr. Gerald Smith Museum of Paleontology Paleontology is a wonderful University of Michigan career, and has many different Emeritus, Curator, Museum of research options. It is an Zoology; amazingly interesting career, but Emeritus, Curator, Museum of it is hard to find a job in Paleontology; paleontology. Emeritus, Professor, Geological Sciences; • museum curator (like Dr. Emeritus, Professor, Ecology and Smith) Evolutionary Biology

ACKNOWLEDGMENTS AND CITATIONS 25

AUTHORS • Dr. Barbara J. Shaw, Colorado State University Extension Western Region Youth Development 4-H STEM K/12 Specialist • Tom Lindsay, retired Portland State University instructor (geology and paleontology); HS science teacher (AP and IB Chemistry, Physics, Biology, and Calculus)

GUEST PALEONTOLOGIST • Dr. Gerald (Jerry) Smith, University of Michigan Museum of Paleontology, Emeritus, Curator, Museum of Zoology; Emeritus, Curator, Museum of Paleontology; Emeritus, Professor, Geological Sciences; Emeritus, Professor, Ecology and Evolutionary Biology

ACKNOWLEDGMENTS • Funding for this project provided by Colorado State University System Venture Capital Fund • CJ Mucklow, Colorado State University Extension Western Regional Director • Dr. Joe Cannon and Marketing Strategies students Berlyn Anderson, Jenna Balsley, Rachel Kassirer, Rachel Richman, Colorado State University, College of Business, for marketing strategies and ST[EMpower] graphics • Doug Garcia, Colorado State University Creative Services Communication Coordinator/ Designer

CITATIONS Information: • Trilobite Speciation Lesson developed by: Shaw, Barbara J. and Lindsay, Thomas L. (2006) Trilobite Speciation: 400- 500 Course Life of the Past at Portland State University, modified for ST[EMpower] Paleontology kits 2019. Sources used in developing this lesson: ○ Amazing site on Trilobites by Dr. Sam Gon III; Retrieved from the internet 7 April 2006: http://www.trilobites.info/index.html • Information, images and drawings are all used from Dr. Gon’s amazing site, unless otherwise denoted: https:// www.trilobites.info/trilobite.htm • Cambrian: https://ucmp.berkeley.edu/cambrian/cambrian.php • Phyla: https://simple.wikipedia.org/wiki/List_of_animal_phyla • Play dough recipe: https://www.iheartnaptime.net/play-dough-recipe/

Images: • Images and drawings from Dr. Gon’s amazing site used with permission, unless otherwise denoted: https:// www.trilobites.info/trilobite.htm • Three Domains: https://upload.wikimedia.org/wikipedia/commons/thumb/7/70/Phylogenetic_tree.svg/440px- Phylogenetic_tree.svg.png • birefringent calcite: https://socratic.org/questions/what-is-the-easiest-way-to-identify-the-mineral-calcite • Compound eye: https://www.humboldt-foundation.de/web/kosmos-humboldtians-in-focus-91-1.html; https:// en.wikipedia.org/wiki/Lens: Dr. Shaw’s demo of focal length with virtual image upside down • Trilobite images: https://assets3.fossilera.com/sp2/37619/oklahoma/620x400/cordania-falcata.jpg; https:// en.wikipedia.org/wiki/Walliserops; https://en.wikipedia.org/wiki/Trilobite • Choloepus didactylus, American Society of Mammalogists Image Library: http://www.mammalsociety.org/ searcHasm_custom_searcHCholoepus%20didactylus • Molly and Sam: my beloved beagles, always in my heart • Peppered Moth: https://en.wikipedia.org/wiki/Peppered_moth_evolution • Nektaspida: https://upload.wikimedia.org/wikipedia/commons/7/7b/Naraoia_spinosa.jpg • Karyotype: https://www.news-medical.net/life-sciences/DNA-Biological-Functions.aspx