The Southwest contributes even more to the diversity of birds. According to the USGS, the Colorado River drainage system is home to numerous species including various chubs, the Colorado squawfish, the razorback sucker and the bonytail.
The Rio Grande system of the Colorado River drainage system is home to chubs, the silvery minnow and shiners. Desert springs serve as habitat for pupfishes, springfishes and poolfishes. An icon of the Southwest, the coyote, serves as a guide to how the classification system works for the vertebrates.
At the phylum level, the coyote belongs to the Chordata, which is distinguished by a nerve chord that passes through the backbone. At the class level, the animal belongs to the Mammalia, the members of which possess fur and nurse their young. At the family level, our guide and his close relatives, collectively called Canidae, typically have elongated faces.
They all bear wolf-like characteristics, and they can interbreed, provided the male and female are of compatible size. A male chihuahua would experience a difficult time mating with a female gray wolf.
Desert coyotes are light gray or tan with a black tip on the tail. Burt and Richard P. The coyote has long played a central part in the folk tales, myths and persona of the peoples of the Southwestern deserts, often taking on the role of clown or adventurer.
In stories recorded by Charles F. Lummis in his Pueblo Indian Folk-Stories, foolish coyote falls for practical jokes played by ravens, blackbirds and a bear. Compassionate coyote saves an abandoned baby, bestowing it upon a mother antelope that has lost her fawn.
Magical coyote jumps through a willow hoop and emerges as a handsome young man. While fellow Canis Mexican gray wolf disappeared until being reintroduced from the Southwestern deserts in historic times, clever, adaptable and bold coyote has increased its population and expanded its range from its native desert basins well up into the mountains.
Thief coyote can make a nuisance of himself. Frank Dobie in Some Part of Myself. The patch was in a valley field only a few hundred yards away from the house.
At night we could hear the coyotes laughing over how juicy the watermelons were. How Are Plants Classified? How to Keep Ice Cold in the Desert. Desert Survival Skills. Get the Best Hotel and Motel Rates. DesertUSA Newsletter -- We send articles on hiking, camping and places to explore, as well as animals, wildflower reports, plant information and much more. Sign up below or read more about the DesertUSA newsletter here.
It's Free. There are many hundreds of different types of phytoplankton. For decades, most scientists have thought that phytoplankton lived only by photosynthesis. It turns out that many of these phytoplankton also eat the way animals do [ 1 ].
Some eat other phytoplankton, some eat bacteria, and some eat tiny animals Figure 2. Some of these mixotroph phytoplankton eat only reluctantly or rarely. Some are aggressive and can stuff themselves full of food! These mixotrophs grow much faster when they can eat and photosynthesize at the same time, compared with when they grow by photosynthesis alone. The ways the mixotrophic phytoplankton eat can be pretty gruesome. Some gobble up entire organisms, while some harpoon their food and suck out the innards using a self-made straw.
Some can make their meal explode, leaving a nutritious soup that they can soak up. Some can even eat other organisms that are much bigger than themselves. Some mixotrophic phytoplankton use poisons to kill what they want to eat. Interestingly, some can make these poisons only when they photosynthesize AND eat at the same time. An example is an organism called Karlodinium. Karlodinium eats other small algae aggressively, but it seems to only eat during daylight.
Why does it not also eat at night? It turns out that Karlodinium makes the poisonous compound that it releases to kill its food during daytime, when it is also photosynthesizing.
Along with phytoplankton, there are other, tiny animal-like organisms in the ocean that are called microzooplankton , because they are small micro- , animal zoo- -like plankton. Microzooplankton eat lots of different things, but when they eat tiny phytoplankton, they can become part-time plants.
How can they do this? One type of microzooplankton eats phytoplankton, but they do not digest the photosynthesizing machinery the chloroplasts ; Figure 3. They keep the stolen chloroplasts and use these to photosynthesize!
Can you imagine the broccoli you eat continuing to photosynthesize in your stomach after you ate it? Some mixotrophic microzooplankton are picky eaters, and become plant-like only by eating their favorite foods.
One type of these picky mixotrophs is a species called Dinophysis , which is found in oceans all over the world. Dinophysis wants chloroplasts from one specific type of microscopic phytoplankton but cannot eat those phytoplankton directly. So Dinophysis eats another mixotroph named Mesodinium that eats the specific phytoplankton with those chloroplasts.
The Dinophysis then pokes a hole into the Mesodinium and sucks all their guts out to finally get the chloroplasts it wants. All our oceans are home to mixotrophic plankton, but different types live in different parts of the ocean or at different times of year.
Some types, such as the Karlodinium , are mainly found along coastal areas, while other types are more common in the open waters of the oceans. Other types of mixotrophic plankton are associated with polar waters or tropical waters. Some are more common during certain seasons—especially summer.
Many mixotrophs grow very well in waters that have become eutrophic enriched with too many nutrients or fertilizers from all of our human wastes [ 4 ].
When we apply fertilizers to lawns or farm land, not all of that fertilizer is used by grass or by crops. Why the recent addition of cephalopods? And how does a species become entitled to ethical protection? The Australian Code of Practice leaves some clues. They focus on four aspects that should be considered in animal research:.
As these are all subjective states of affairs, it is difficult to assess whether or not an animal experiences them. We can usually identify these things in other humans, as they act in a way that we would when distressed ourselves — but animals adapted to different lifestyles may behave differently to us. Tourists watching a captive elephant swaying may think it is being playful, when in fact the animal is distressed.
Even in closely related animals, such as chimpanzees, some behavioural displays are difficult for us to interpret. If this is the case, what hope do we have for identifying a stressed-out jellyfish?
Because of these limitations, it appears that the NHMRC have resorted to a physical account of pain and distress. According to the code:. All vertebrates possess the anatomical and neurophysiological components for the reception, transmission, central processing and memory of painful stimuli.
Some of these features are also present in some higher-order invertebrates, such as octopus and squid. This, together with analyses of animal behaviour, supports the view that an animal may have subjective experiences of pain similar to those of humans.
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