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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
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)
Liwi
Nihoa finch
Founder species:
Liwi:
Nihoa finch:
CAM
moderate
high
low
Bmp4
moderate or low
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
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
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?
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:
3
5
5
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:
1
1
2
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
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