2122 Apenheul V3 (English version)

• Biologie
• Middelbare school
• havo, vwo
• Leerjaar 3

Excursion Apenheul 2021

Write your names & class here.

Go to black-capped squirrel monkey

Don't forget to look around for other monkeys & apes!

Black-capped squirrel monkeys can live in groups up to 200 individuals. Why is it an advantage to live in such a large group?

The squirrel monkey has a nasty habit. He pees on his own hands and feet! Then he smears the pee all over his body. His tail gets soaking wet. Its tail and its wet hands and feet leave a kind of stamp on the branches.

What do you think is the reason for this?

Watch the following video

If you are doing physical worksheet, go to YouTube and search for the following video:

'Doodshoofdaapjes springen

een gat in de lucht'

What do you think is the function of their tail after watching this video?

Go to the black howler monkey
(zwarte brulaap) 

Don't forget to look around for other monkeys & apes!

Watch the following video

If you are doing physical worksheet, go to YouTube and search for the following video:

'Brulapen in concert'

It's all in the name: black howler monkeys can howl (brul) loudly. Their howl sounds like a loud burp and can be heard up to 2 miles (3 km) away!
The leader of the group starts and the rest joins in. As they howl, they often sit in a row.
What's the function of this roar? Name at least two reasons.

The body of a black howler monkey is adapted to be able to howl as loud as possible.
What adaptation do you notice when you look at his/hers body, that facilitates the loud howling?

Howler monkeys can seem a little lazy. Compared to other spider monkey species, they spend a large part of the day resting. They mostly eat leaves while other spider monkeys eat ripe fruits. Ripe fruits contain a lot of glucose, while leaves contain a lot less glucose.
Explain how the howler monkey's diet affects their daily activity and why.

Go to the bonobos

Don't forget to look around for other monkeys & apes!

The bonobo is the closest to man of all apes.
Choose an active Bonobo and set a timer of 3 minutes:
write down what your monkey does in those 3 minutes.

Which of the things your monkey has done looks like the behavior of humans?

What differences between a bonobo and a human can you see? Write down differences in behavior (gedrag) as well as in appearance (uiterlijk).

Bonobos often have sex with each other. They do it to resolve a conflict (ruzie) or just to relax. Within a Bonobo group, everyone does it with everyone, except sons with their mothers.
This is quite different from most people. Why do you think people live in pairs of two people and are not as free as the bonobos?

Go to the ringtailed-lemurs

Don't forget to look around for other monkeys & apes!

Ring-tailed lemurs are highly territorial.
What does that mean?

1. They defend their habitat against lemurs from other groups.
2. They do not tolerate any other animal species in their habitat.
3. Males and females only come together for mating.

The ring-tailed lemur's tail is longer than its body

1. True
2. False

Watch the following video

If you are doing physical worksheet, go to YouTube and search for the following video:
'Lemur stink fight Dudley Zoo'

Male ring tailed lemurs put smells, from glands in their bottoms, on their tail and wave it at rivals. It’s known as ‘stink fighting’!
They also use it to wave at the lady lemurs. What could be the function of this?

Go to the orangutans

Don't forget to look around for other monkeys & apes!

Some adult male orangutans develop flaps of fatty tissue on both sides of their face - known as flanges - which develop when they're fully mature, at around 35 years old.
Find a male organgutan and take picture of him.

Orangutans find their food both on the ground and in the trees. Observe these monkeys for a while. Describe how they look for and eat food (which body parts and senses do they use for this)?

Compare the human teeth with those of the orangutan. Although the orangutan does not eat meat, it does have large canines (hoektanden). Why do you think this is?

Orangutans are smart animals. To challenge these monkeys, the Apenheul has added extra stimuli (prikkels) to the orangutan's enclosure. This makes them less bored.
What stimuli can you find?

Go to the gorilla's

Gorillas stick to a mainly vegetarian diet, feeding on stems, leaves and fruits. Western lowland gorillas, however, also have an appetite for termites and ants, and break open termite nests to eat the larvae. 

Gorillas look a lot like us. Their digestive system (verteringstelsel) has a lot in common with ours. As you can see gorillas have big bellies. Their extra long intestines have to fit into them.
Why is it that they have such long intestines?

Gorillas live together in groups of 5 to 20 gorillas. There is one leader in the group, a male. He lives together with the females and their young. The gorilla leader makes sure there is peace in the group and protects them.
Observe the group gorillas for a few minutes and try to spot the leader. How can you recognize the leader?

Do you see any behavioral (gedrag) differences between the leader and the rest of the group?

Go to the Colombian spider monkeys

Don't forget to look around for other monkeys & apes!

Count the number of fingers this monkey has.
Why is this useful when climbing?

What evolutionary benefit do spider monkeys gain from having a prehensile tail (grijpstaart)? 1

If you look closely, you will see a pink appendix (aanhangsel) in the females.
Search online for what this appendix is.

1. Intestine
2. Clitoris
3. Penis
4. Small tail

Observe the spider monkeys for 3 minutes.
Can you see any spider monkeys in friendship groups? Describe how you can see this.