Honeycreepers are a group of birds found only in the Hawaiian Islands that appeared rapidly between 5 and 3 million years ago. They occupy a variety

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1 Honeycreepers are a group of birds found only in the Hawaiian Islands that appeared rapidly between 5 and 3 million years ago. They occupy a variety of niches throughout the various islands of the archipelago and the diversity of their beaks reflects the variety of their diets, though most have adopted some form of nectar feeding. The closest living relative to the honeycreeper is the Eurasian rosefinch and it is generally agreed that honeycreepers evolved from an ancestral rosefinch that arrived in the Hawaiian Islands somewhere between 7 to 5.8 million years ago. The phylogeny on the right depicts the relationship of honey creepers to other similar birds. Refer to the information in the text above as well as the figure to the right when answering the following questions: Which type of speciation process most likely led to the creation of the first honeycreeper species in the Hawaiian Islands (be as specific as possible)? (4) Allopatric speciation via dispersal and colonization What term best describes the pattern of the clade representing honeycreepers on the phylogeny above? (2) Polytomy or star phylogeny What mechanism is most likely responsible for promoting the adaptive radiation of this clade? (2) Dispersal/colonization What taxon would be the best outgroup to the honeycreeper clade? (2) eurasian rosefinch As mentioned previously, several species of honeycreepers have a diet largely made up of nectar which they extract from the rich variety of flowering plants found throughout the Hawaiian Islands. They all have somewhat elongated beaks (relative to the more traditional finch beak) that allows them to do this. The figure on the right shows the relationship between several species of nectar feeding honeycreepers and the rosefinch as well as pictures of the head and beak morphology for each. Information is also provided on which islands each species of honeycreepers can be found. What type of microevolutionary mechanism most likely was responsible for the development of the nectar feeding beak from the ancestral finch beak (be as specific as possible)? (2) directional selection Using the information contained in the phylogeny from the previous question, indicate underneath each species category how many distinct species of nectar feeding honeycreepers can be identified for the following categories of species. If the number cannot be determined from the available information simply state unable to be determined (6) Biological species Phylogenetic species Morphological species unable to determine 5 5

2 Name/SID Again, referring to the phylogeny of nectar feeding honeycreepers on the previous page, indicate whether the following groups are mono, para, or polyphyletic: (3) Liwi & Amakihi species 1: polyphyletic Ancestral rosefinch, Eurasian rosefinch, Liwi, Akohekohe, Apapane,: paraphyletic Akohekohe & Apapane: monophyletic CaM and Bmp4 are genes that regulate the development of beaks in birds. The amount of CaM expression during development controls the relative length (low - short, moderate - intermediate, high - elongate) of the beak while the amount of Bmp4 expression during development controls both the relative depth and width of the beak (low shallow & narrow, moderate medium for both, high deep & wide). The picture below shows two honeycreepers, the Nihoa finch which eats bird eggs and nuts and the Liwi which eats nectar, which both descended from an ancestral species that resembled the bird in the middle. For each bird suggest the level of expression (low, moderate, high) of both CAM and Bmp4 during development (6) Nihoa finch Liwi CAM Bmp4 Founder species: moderate moderate or low Liwi: high low Nihoa finch: low high What micro-evolutionary process could be responsible for causing the differences in the relative amount of expression of the two genes that you indicated in your answer above? (2) Mutation, specifically to the regulatory gene that controls how long each gene is turned on Bird beak morphology has a large influence on bird singing. Deep beaks place a greater constraint on the trill rate than do shallower beaks and this results in very different mating songs in birds with these type of beaks. If Liwis and Nihoa finch evolved on the same island, what general type of speciation is likely to have occurred to produce them? (2) Sympatric speciation What reproductive isolating mechanism is likely to have facilitated the type of speciation? (2) Behavioral disruption Would this be an example of pre or post zygotic reproductive isolation? (2) prezyotic

3 Terrestrial plants are thought to have appeared on land around 470 million years ago and are thought to have evolved from green algae. Several new morphological innovations such as stems, roots and leaves, and vascular tissue (tissues that conduct water from the roots to the leaves and food from the leaves to the roots) were key adaptations that facilitated this transition to terrestrial living. Below is a character matrix for several photosynthesizing organisms and an unlabeled cladogram. Using the information in the character matrix, determine where each organism should be placed on the cladogram and then insert where in the tree each character in the matrix should be placed (using a dash and the character name) in order to indicate when this trait appeared in the evolution of this lineage. (6) Which taxon would be the outgroup to the clade that was made up of terrestrial plants? (2) seaweed What would be a sympleisomorphy for ferns, conifers and Irises? (2) vascular tissue What would be a symanpomorphy that distinguishes mosses and ferns from the nearest common ancestor? (2) stems Some brown algae (seaweed) such as giant kelp have vascular tissue that allow them to transport food from the blades at the surface to the rootlets that anchor them to the bottom up to 60 feet deep. What term would best describe the relationship of this vascular tissue to the vascular tissue found in the terrestrial plants in the matrix/phylogeny above and what would we call the process by which both these traits were produced? (4) Term: homoplasy or analogous structure Process: convergent In which eon of Earth s history did terrestrial plants emerge? (1) Phanerozoic In what eon of Earth s history did photosynthesis first appear (1) archaen Which of the taxa in the matrix table above would be least likely to make a fossil due to a taxonomic bias? (1) Euglena

4 Horses, donkeys, and zebras are grazing mammals that are members of the family Equidae. The earliest fossils of ancestral horses were no bigger than dogs and appeared in North America some 50+ million years ago during the radiation of placental mammals. The early ancestors of the modern horse walked on several spread-out toes, an accommodation to life spent walking on the soft, moist grounds of primeval forests. As grass species began to appear and flourish, the equids' diets shifted from foliage to grasses, leading to larger and more durable teeth. At the same time, as grasslands began to appear, the horse's predecessors needed to be capable of greater speeds to outrun predators. This was attained through the lengthening of limbs and the lifting of some toes from the ground in such a way that the weight of the body was gradually placed on one of the longest toes, the third. What was the likely mechanism that caused the rapid radiation of mammals in the early Cenozoic? (2) Adaptive radiation following a mass extinction event What was the era that immediately preceded the Cenozoic? (2) Mesozoic What type of microevolutionary process most likely drove the change in limb length and body & tooth size in horse evolution (be as specific as possible)? (2) Directional selection What would be a synapomorphy that distinguish modern Equids from earlier equids such as Mesohippus? (2) Lifting of toes, enlargement of teeth, elongation of teeth Modern equids all belong to the Genus Equus and include the domesticated horse (Equs caballus), donkeys (Equus asinus), and zebras (Equus zebra, burchellii, and grevyi). Equus appeared in North America around 5-6 million years ago and then migrated to Asia over the Alaska-Russia land bridge about 2.5 million years ago. Some entered Africa and diversified into the modern zebras. Others spread across Asia, the Mideast, & N. Africa as desert-adapted donkeys. Still others spread across Asia, the Mideast, and Europe as the true horse, E. caballus. What type of speciation is suggested by the initial spread of the ancestral Equus across the Alaska- Russia land bridge (be as specific as possible)? (4) Allopatric speciation via dispersal and colonization BQ2: What is one difference between gradualism and punctuated equilibrium?

5 Name/SID The figure on the right shows a phylogeny of modern living Equids. In this tree, are zebras poly, para, or monophyletic? (2) monophyletic Zebras are only found in the wild in Africa. They used to roam the entire continent, but now are found only in the south. There are three main species of zebras each with distinct coat patterns, and they can all interbreed to produce viable offspring: They are the plains zebra (Equus burchellii), Grevy's zebra (Equus grevyi) and mountain zebra (Equus zebra.) Zebra breeding behavior is very much like feral horses, feral donkeys and wild asses. Zebras can breed not only with other types of zebras, but also with horses, ponies and donkeys, as all of these species engage in the same sexual behavior. However, like mules (the offspring of horses and donkeys), the offspring of zebras and either horses or donkeys are sterile. Based on this information and the phylogeny above, distinguish how many of the following species categories are present in modern living Equids: (3) Biological Species: Phylogentic species: Morphospecies: Although zebra species may have overlapping ranges, they do not typically interbreed and hybrids between species are rare. What type of speciation does this suggest has occurred? (2) Sympatric speciation What term best characterizes the rarity of hybrids and what does this suggest about the fitness of hybrids relative to either parent species? (4) Reinforcement it suggests that the fitness of hybrids is less than either parent species Sponges have an extremely simple body design and lack true multicellular tissues. Anemones have a simple radially symmetrical body design with only two different types of tissue. Flatworms have a more complex bilaterally symmetrical body design with three types of tissue. Armed with this knowledge, consider the information on Hox genes for these 3 organisms presented in the figure to the right and answer the following questions: How many orthologs do the following share (3) Sponges & Anemones: Sponges & Flatworms: Anemomes & Flatworms: What term could be used to describe the relationship between the group 3 and central hox genes in flatworms? (2) paralog What do the data suggest with respect to the relationship between hox genes and body complexity? (4) Increased numbers of hox genes corresponds to more complex body structure BQ 3: What process would not act on (affect) mutations to neutral DNA? Natural selection

6 Now consider the figure on the left that shows the embryology of a fish vs a rabbit. Assuming that each species has a similar number of hox genes, answer the following questions: What might account for the different pathways of development (ie why if they have the same number of hox genes do they develop into different body plans)? (2) Mutations that affect the spatial and or temporal expression of those hox genes Rabbits and fish both have gill slits early in development yet as adults, fish breathe water with gills and rabbits breathe air with lungs. Would it be proper to refer to gill slits in these two organisms as a homoplasy or if not, what would be an appropriate term to describe the relationship of this trait in these two organisms? (2) No, these constitute homologous structures List the type of fossil depicted in each of the lettered photographs: (4) A: B: C: D: Compression cast fossil organically preserved permineralized Carbon rich film Indicate the eon (Proterozoic, Archaen, Phanerozoic, Hadean) in which each of the following events first occurred: (6) Massive coal forming forests: Phanerozoic Chemical selection: Hadean Photosynthesis: Archean Cretaceous extinction: Phanerozoic First flowering plants: Phanerozoic Duoshaunto fossil fauna: Proterozoic