Tropical mammals midterm

Tropical ecosystems surround the equator in a band of _________ degrees latitude that stretches from the Tropic of Cancer in the Northern Hemisphere to the Tropic of Capricorn in the Southern Hemisphere.

47

Not all ecosystems found between the Tropic of Cancer and Capricorn are tropical.  In addition to latitude, __________ also determines whether an ecosystem will be tropical.

elevation

A simplified version of the Life Concept (Holdridge 1947) suggests two climatic variables can be used to determine what sort of terrestrial ecosystem will occur in any area on Earth.  These two variables are ___ and ___.

Temperature and precipitation

Tropical ecosystems occur at temperatures above __________.

24C

Savannas undergo constant changes in amount of grass cover and woody vegetation. Such changes are related to the effects of 1) varying ___ amounts 2) ___ intensity, and 3) ___ frequency

rainfall, fire, grazing

A plant that is adapted to survive hot and periodically dry conditions is __________.

Xeromorphic

Stranglers (Ficus spp.) are a type of __________.

hemiepiphyte

__________ are a type of epiphyte (three types were mentioned in class).

Orchids, Ferns, or bromelids

Many tropical trees exhibit a unique characteristic termed __________, meaning that the flower and subsequent fruits are produced directly from the wooded trunk, rather than from the canopy branches.  

cauliflory

Tropical rain forests soils are generally nutrient rich.

False

What is the name given to the process by which organisms better adapted to their environment survive and reproduce?

Natural Selection

If you were to ask the question, “Why do the world’s 71 extant lemur species occur exclusively on the island of Madagascar?,” what would you be interested in?

Historical Biogeography

The geographical separation of a population that results in a pair of closely related species is known as what?

Vicariance

Which concept defines a species as “populations of actually or potentially interbreeding organisms?”

Biological Species Concept

The latitudinal diversity gradient states that species diversity is lowest near the poles and increases towards the equator

True

The theory that suggests there is high biodiversity in the tropics as a result of the physical environment being more diverse than in more temperate regions is know as ______________?

Theory of Spatial Heterogeneity

____________ is an interaction between two species in which one benefits and the other neither benefits or is harmed.

Commensalism

What symbiotic relationship can lead to obligate interdependencies?

Mutualism

____________ is the biogeographic phenomenon in which a species or larger clade occurs only in a restricted area.

Endemism

Early biogeographers did not know about plate tectonics and continental drift.  Therefore, they attempted to explain how species dispersed from their centers of origin to other continents in a variety of ways.  What is one of the ways in which they thought this dispersal occurred?

Broad Corridor, Land bridge, filter bridge, sweepstakes route, accidentally transported, raft, or wind

Interspecific competition can take two forms, what are they?

Exploitation competition and interference competition

Gause suggested that complete competitors cannot coexist.  What is the name give to this principle?

Competitive exclusion

Niche partitioning is the result of two process that may operate simultaneously.  These processes are ___ and ___.

Interspecific Competition and Ecological Specialization

Carnivores generally do not select for particular prey species.  However, some tropical species do seem to select for prey species based on _________.

Body weight

A herbivore that is restricted to feeding on only a few plant species is _________.

Stenophagous

Animals that are brightly colored or stand out dramatically as a warning or advertisement are exhibiting ___________.

Aposematism

Bats controlling arthropod pests and in turn reducing herbivory and enhancing plan fitness is an example of a _________ effect

top-down

A ___ species has a uniquely strong influence on a food web, such that its removal causes a ___ cascade”

Keystone and trophic

What is the basal mode of feeding among mammals?

Insectivore

What name is given to mammals whose diet is primarily comprised of ants and termites?

Myrmecophagous

What name is given to the complex bony structure found in the tip of the penis of some mammals?

Baculum

If a mammal had the following dental formula, how many lower incisors would it have?

0/3, 0/0, 3/3, 3/3

6

In carnivores, the masseter muscle is typically larger than the temporalis muscle.

False

What is the name given to the shearing teeth found in carnivores?

Carnassial/Carnassial pair

What type of uterus is seen in most bats, primitive primates, pangolins, and elephants?

Bicornuate

Which of the following mammals has testes that are held within the abdominal cavity?

Tree sloth

In foregut fermenters, the cud is regurgitated from which chamber of the stomach?

Reticulum

In herbivorous mammals, which tooth type is absent or reduced?

Canines

What name is given to mammal hairs that attain a fixed length before being shed and replaced?

Definitive

From what layer of skin are mammal hairs derived?

Epidermis

Hair color in mammals is determined by the distribution and density of  ______________.

Melanin

The skin, or integument, is the interface between a mammal and the external environment.  Its primary functions are ___ and ___.

Water conservation, insulation

Eumelanin gives mammal hair a red or yellow color.

False

Which of the following is the most primitive form?

Claws

Which of the following have a reduced or lost clavicle?

Felidae

What name is given to mammals whose mode of locomotion involves jumping or ricocheting?

Saltatorial

What name is given to the vertebrae that comprise the tail of mammals?

Caudal

A true horn is comprised of a core of dermal bone with a keratinized sheath.

True

Most mammals have ___cervical vertebrae. The exception are the ___ that have 5 to 9.

seven, sloth

Bushmeat is the #1 threat to biodiversity globally.

False