Maternal care in scorpions - suggested answers

Issue 7, December 1996

1. approximately 10 em per s (or 30%)

2. 30.5%

3. 0.21 g

4. Fig. 2 - there is a negative correlation between carrying speed and the number of litter, i.e. as the number of litter increases the carrying speed decreases

Fig. 3 - there is a negative correlation between the variables, i.e. as the mass of the litter increases the carrying speed decreases

[a quantitative citation of the data is equally acceptable]

5. they may not make it to the nearest cover before a predator catches them because of the weight on their back

- their movement may draw the attention of a predator to them

- their sprinting may dislodge one, or more, of the young who could be taken by a predator

6. they could have learnt that being prodded by a pair of forceps is not a real predator and so would not have sprinted in the same way as they did on the first trial

- the fact that the apparatus was so unlike their natural environment may have caused them to behave in a non-normal way, especially on a second or third occasion [reject 'exhaustion' as an answer]

7. a random sample is one in which, in theory at least, every scorpion in that area could have been included in the sample

- presumably sonic animals (here scorpions) are easier to catch than others

8. this is a reproductive process in which the embryo develops inside the body of the mother and from which it obtains all its nourishment

9.adv- can control variables - can use apparatus more easily - 24 hour recording is possible

Disadv - don't see 'natural' behaviour - some research may raise ethical issues - may get 'demand characteristics' shown by subjects - danger of extrapolating behaviour to that shown in the field